Words that start with O
Open day
An open day is an event where a institution or organization opens its ...
Open diapason
Open diapason refers to a range of pitches produced by a musical instr...
Open die
Open die forging is a metalworking process where the metal is shaped b...
Open door
"Open door" signifies opportunity and accessibility to new possibiliti...
Open doors
"Open doors signify opportunities for growth and new experiences."...
Open educational resource
Open educational resources are educational materials that are freely a...
Open enrollment
Open enrollment is the period during which individuals can freely el...
Open field
An open field refers to a vast expanse of land with no buildings or st...
Open fire
The open fire refers to the act of igniting flames that are not contai...
Open flash
Open flash is a photography technique where the camera's shutter is le...
Open fracture
An open fracture is a type of bone fracture where the skin is broken, ...
Open frame
Open frame refers to a design that incorporates a frame structure with...
Open game
The term "open game" refers to a match or competition where the outcom...
Open house
An open house is an event where a property is available for viewing by...
Open house, keep
An open house is an event where a property is available for potential ...
Open housing
Open housing promotes fair and equal access to housing opportunities f...
Open interval
An open interval is a set of real numbers defined by two endpoints tha...
Open juncture
Open juncture is a linguistic term referring to the spacing between wo...
Open learning
Open learning is a flexible, inclusive approach to education that allo...
Open letter
An open letter is a public message addressed to a specific person or...
Open loop
Open loop refers to a system where external feedback is not used to ad...
Open market
An open market refers to a free market where goods and services are tr...
Open marriage
An open marriage is a form of consensual non-monogamy where both partn...
Open mic
An open mic is an event where people can perform freely without any re...
Open mike
Open mike refers to a performance format in which anyone from the audi...
Open mind
Having an open mind means being receptive to new ideas, perspectives, ...
Open one's eyes
"Open one's eyes means becoming aware of something previously unnotice...
Open one's heart to
To open one's heart to someone means to be vulnerable and candid in sh...
Open one's mouth
To open one's mouth means to speak or express oneself....
Open order
An open order refers to a trading order that has not been filled or ca...
Open plan
Open plan means a layout that eliminates physical barriers between dif...
Open policy
Open policy means a transparent and accessible approach to decision-ma...
Open position
An open position refers to a job vacancy that needs to be filled withi...
Open primary
An open primary allows voters to choose which party's primary election...
Open prison
An open prison is a type of correctional facility where inmates have m...
Open punctuation
Open punctuation refers to a writing style that does not use any unnec...
Open question
An open question is one that cannot be answered with a simple yes or n...
Open quote
The meaning of open quote is to signal the beginning of a direct quota...
Open registry
Open registry allows anyone to register a domain name without restrict...
Open sandwich
An open sandwich is a type of sandwich consisting of one slice of brea...
Open sea
The open sea refers to the vast expanses of ocean unobstructed by land...
Open season
Open season refers to a period where hunting or fishing is permitted f...
Open season on
Open season on means the period of time when hunting or shooting a par...
Open secret
An "open secret" is a known fact or piece of information that is widel...
Open sentence
An open sentence is a mathematical statement with variables that can b...
Open sesame
"Open sesame" means a phrase that magically opens doors or reveals hid...
Open set
An open set is a set in which every point has a neighborhood entirely ...
Open shop
Open shop refers to a workplace where employees are not required to ...
Open side
The meaning of open side is exposed or accessible to view or access....
Open sight
Open sight means having a clear and unobstructed view or perception, w...
Open slather
Open slather means a situation where unrestricted access or opportunit...
Open space
Open space refers to an area of land that is unobstructed or unoccupie...
Open stance
An open stance refers to having a mindset or approach that is receptiv...
Open stock
Open stock refers to items available for purchase individually, rather...
Open string
An "open string" refers to a string on a musical instrument that is pl...
Open system
An open system refers to a system that interacts with its environment ...
Open texture
Open texture refers to the flexibility or incompleteness of language, ...
Open the door to
Open the door to new opportunities and possibilities by being open-min...
Open trailer
An open trailer is a type of trailer that is not enclosed, typically u...
Open union
An open union allows for a diverse range of members to join and partic...
Open universe
An open universe refers to a cosmological model where the universe wil...
Open University
The Open University is a flexible educational institution that allows ...
Open up
To reveal or share one's thoughts or feelings with someone....
Open verdict
An open verdict is a ruling where the cause of death remains undetermi...
Open with
To be open means to be accessible, inclusive, and transparent....
Open-and-shut
"Open-and-shut" means a situation or case that is clear and easy to un...
Open-angle glaucoma
Open-angle glaucoma is a progressive eye disease characterized by slow...
Open-cast
Open-cast mining is a surface extraction method where mineral resource...
Open-concept
Open-concept refers to a spacious layout in a building where rooms flo...
Open-cut
Open-cut refers to a mining technique where minerals are extracted fro...
Open-cut mining
Open-cut mining is a surface mining technique that involves removing l...
Open-end
Open-end refers to a flexible or customizable structure that allows fo...
Open-end mortgage
An open-end mortgage allows borrowers to increase their loan amount if...
Open-ended
Open-ended questions allow for a wide range of possible responses and ...
Open-eyed
"Open-eyed" means being aware and observant, with a focus on awareness...
Open-faced
Open-faced means a type of sandwich with only one slice of bread, typi...
Open-heart surgery
Open-heart surgery is a procedure in which the surgeon operates on the...
Open-hearted
Open-hearted means being genuine and sincere in one's emotions and act...
Open-hearth
Open-hearth refers to a method of steel-making that involves using an ...
Open-hearth furnace
An open-hearth furnace is a type of furnace used for steelmaking that ...
Open-hearth process
The open-hearth process is a method of producing steel by melting pig ...
Open-jaw
"Open-jaw" in travel refers to a flight itinerary where the traveler r...
Open-line
An open-line refers to a direct communication channel that is accessib...
Open-market operations
Open-market operations refer to the buying and selling of government s...
Open-minded
Being open-minded means being receptive to new ideas and perspectives....
Open-mouthed
The term open-mouthed refers to being surprised or astonished....
Open-pit
An open-pit mine is a type of surface excavation where minerals are ex...
Open-pollinated
Open-pollinated seeds are those that are pollinated naturally by wind,...
Open-reel
Open-reel refers to a type of magnetic tape storage system where the t...
Open-reel tape
Open-reel tape is a magnetic tape storage medium that uses a reel to h...
Open-shelf
Open-shelf furniture refers to a style where items are displayed on sh...
Open-sided
The term "open-sided" refers to a structure that is partially exposed ...
Open-source
Open-source refers to software that is freely available for anyone to ...
Open-stack
Open-stack is a platform that provides open-source software for buildi...
Open-standard
Open-standard refers to a set of guidelines or criteria that are publi...
Open-timbered
Open-timbered refers to a structure with exposed wooden beams and fram...
Open-web
Open-web refers to a structural system where the web elements are open...
Openable
The term "openable" indicates that something can be opened or accessed...
Opencast mining
Opencast mining is a surface mining technique that involves extracting...
Opener
An opener is an introduction or beginning, setting the tone for what f...
Openhanded
Openhanded means to be generous or liberal with giving resources or he...
Opening
The meaning of opening refers to the beginning or initiation of someth...
Opening night
Opening night is the premiere performance of a show or event....
Opening time
The meaning of opening time is the designated hours during which a b...
Openness
The concept of openness refers to the willingness to embrace new ideas...
Openwork
Openwork is a decorative technique that involves creating patterns or ...
OPer.
OPer is a software developer who specializes in operations....
Opera
Opera is a theatrical form of art combining dramatic acting, singing, ...
Opéra bouffe
Opéra bouffe is a genre of musical theater that combines comedy with o...
Opera buffa
Opera buffa is a comedic opera genre characterized by everyday charact...
Opera cloak
The meaning of opera cloak can be defined as a dramatic and elegant ga...
Opéra comique
Opéra comique is a genre of opera that features comic elements and spo...
Opera glasses
Opera glasses are small binoculars used to enhance the viewing experie...
Opera hat
An opera hat is a collapsible top hat that can be worn to formal occas...
Opera house
An opera house is a theater specifically designed for the performance ...
Opera seria
Opera seria is a dramatic form of opera that focuses on serious and no...
Opera window
The opera window is a small window usually found on the C-pillar of a ...
Operable
Operable means able to be used or functional....
Operagoer
An operagoer is a person who regularly attends opera performances....
Operand
An operand is a symbol or quantity that is operated on in a mathematic...
Operant
Operant conditioning is a type of learning in which behavior is modifi...
Operant conditioning
Operant conditioning is a learning process in which behavior is modifi...
Operant learning
Operant learning is a type of learning in which behavior is modified t...
Operate
The word operate means to function or work in a specified manner....
Operatic
Operatic means dramatic or over-the-top, often involving passionate si...
Operating
Operating means carrying out a set of planned actions or activities to...
Operating budget
An operating budget is a financial plan that outlines expected revenue...
Operating income
Operating income is the profit made from a company's operating activit...
Operating room
An operating room is a specialized facility in a hospital where surgic...
Operating system
An operating system is a software that manages computer hardware and p...
Operating table
An operating table is a specialized medical equipment used for surgica...
Operating theatre
An operating theatre is a designated area within a hospital where surg...
Operation
Operation is a set of coordinated activities conducted for a specific ...
Operation Barbarossa
Operation Barbarossa was the code name for Nazi Germany's invasion of ...
Operation Desert Storm
Operation Desert Storm was a military operation led by the United Stat...
Operation Overlord
Operation Overlord refers to the codename for the Allied invasion of N...
Operation Sealion
Operation Sealion was the code name for Nazi Germany's plan to invade ...
Operational
Operational means relating to the operation or functioning of somethin...
Operational amplifier
An operational amplifier is a high-gain electronic voltage amplifier w...
Operational calculus
Operational calculus is a mathematical method that combines algebraic ...
Operationalism
Operationalism is the philosophical concept that defines meaning in te...
Operationalize
To operationalize means to put into practice or implement a plan or id...
Operations research
Operations research is a field that focuses on using mathematical mode...
Operations room
The operations room is a centralized location where decisions are made...
Operative
Operative means functioning or in effect....
Operatize
The term "operatize" means to transform something into an operation or...
Operator
An operator is a symbol or function that performs a specific operation...
Operatory
An operatory is a designated workspace for dental procedures....
Opercle
An opercle is a bony flap of tissue that covers and protects the gills...
Operculate
Operculate means having a lid or covering that can be opened or closed...
Operculum
The operculum is a protective covering or lid found on certain organis...
Opere citato
Opere citato refers to a citation previously mentioned in the text....
Operetta
Operetta is a form of musical theater that combines music, dialogue, a...
Operon
An operon is a cluster of genes that are transcribed together into a s...
Operose
Operose means involving a lot of effort and hard work....
Opgefok
Opgefok means agitated or worked up in Afrikaans....
Ophelia
Ophelia is a character in Shakespeare's Hamlet who embodies tragedy an...
Opheltes
The meaning of Opheltes lies in its tragedy, as a child's life is lost...
Ophicleide
The ophicleide is a brass instrument that was commonly used in the 19t...
Ophidian
Ophidian refers to something relating to snakes....
Ophidiid
Ophidiid refers to a type of fish belonging to the family Ophidiidae, ...
Ophiolatry
Ophiolatry is the worship of snakes or serpent deities....
Ophiolite
Ophiolite is a sequence of oceanic rocks emplaced during tectonic proc...
Ophiolite suite
An ophiolite suite is a sequence of rocks that represent a segment of ...
Ophiology
Ophiology is the study of snakes and reptiles....
Ophiophagous
Ophiophagous means snake-eating or feeding on snakes....
Ophir
Ophir is a biblical location known for its wealth and resources, speci...
Ophite
Ophite refers to a type of mineral displaying a snake-like appearance,...
Ophitic
Ophitic refers to a texture in rocks characterized by the presence of ...
Ophiuchus
Ophiuchus is a constellation representing a serpent bearer, with serpe...
Ophiuroid
Ophiuroid means "snake-like" referring to the long, slender arms of br...
Ophthal.
Ophthal. refers to the study and practice of medicine related to the e...
Ophthalm-
The term ophthalm- pertains to the eye or vision, with its origin root...
Ophthalmia
Ophthalmia is a disease characterized by inflammation of the eyes....
Ophthalmia neonatorum
Ophthalmia neonatorum is a neonatal eye infection contracted during ch...
Ophthalmic
Ophthalmic refers to anything related to the eye....
Ophthalmic optician
An ophthalmic optician is a professional who specializes in fitting an...
Ophthalmitis
Ophthalmitis is inflammation of the eye tissues, typically caused by i...
Ophthalmo-
Ophthalmo- refers to the eye....
Ophthalmodynamometer
An ophthalmodynamometer is a device used to measure the pressure withi...
Ophthalmol.
The ophthalmol prefix refers to the field of medicine related to the e...
Ophthalmologist
An ophthalmologist is a medical doctor specializing in the diagnosis a...
Ophthalmology
Ophthalmology is the medical specialty focused on the diagnosis and tr...
Ophthalmometer
An ophthalmometer is a medical device used to measure the curvature of...
Ophthalmoscope
An ophthalmoscope is a medical device used by healthcare professionals...
Ophthalmoscopy
Ophthalmoscopy is a medical technique that involves examining the back...
Ophüls
Ophüls is a term that refers to a German director known for his elegan...
Opiate
An opiate is a narcotic drug derived from opium or a synthetic analog,...
Opiatic
The term opiatic refers to something that resembles or relates to opiu...
Opine
Opine means to express one's opinion or belief....
Opined
Opined means to express one's opinion or belief about something....
Opinicus
An opinicus is a mythical creature often depicted as a lion with the w...
Opinion
Opinion is a subjective belief or view that one holds about a particul...
Opinion poll
An opinion poll is a survey conducted to gather data on public opinion...
Opinionated
Opinionated means having and expressing strong opinions in a forceful ...
Opinionative
Opinionative means forming or expressing strong opinions or beliefs....
Opinioned
Opinioned means having a strong belief or viewpoint that is firmly hel...
Opioid
An opioid is a type of medication that is used to relieve pain by inte...
Opioid epidemic
The opioid epidemic refers to the widespread misuse and addiction to p...
Opistho-
Opistho- means behind or backward....
Opisthobranch
Opisthobranch refers to a type of marine gastropod characterized by ha...
Opisthodomos
Opisthodomos refers to the rear chamber of a Greek temple, often used ...
Opisthognathous
Opisthognathous refers to an animal with a reversed position of its ja...
Opisthograph
An opisthograph is a manuscript or piece of writing that is written on...
Opisthosoma
Opisthosoma refers to the abdomen of arachnids, characterized by its l...
Opium
Opium is a powerful narcotic derived from the poppy plant that produce...
Opium den
An opium den is a place where individuals gather to smoke opium, a hig...
Opium poppy
The opium poppy is a plant famous for its poppy seeds, which are commo...
Opium War
The Opium War was a conflict between China and Britain sparked by the ...
Opium Wars
The Opium Wars were a series of conflicts primarily fought over the op...
Opiumism
Opiumism is the addiction to opium or its derivatives that results in ...
OPM
OPM, short for Other People's Money, refers to using external sources ...
Opole
Opole is a city in southern Poland known for its historic architecture...
Oporto
Oporto is a city in Portugal famous for its beautiful riverfront and h...
Opossum
An opossum is a marsupial known for its distinctive appearance and abi...
Opossum block
An opossum block is a shelter used primarily by opossums to seek refug...
Opossum shrimp
An opossum shrimp is a crustacean that resembles a small shrimp and ...
Opotherapy
Opotherapy is the treatment of disease by using extracts of organ tiss...
Opp.
Opp. means opposite or opposition, showing contrast or contradiction....
Oppenheim
Oppenheim is a financial thriller novel about a wealthy investment ban...
Oppenheimer
Oppenheimer explores the life and impact of the renowned physicist J. ...
Oppenheimer, J. Robert
J. Robert Oppenheimer was a brilliant physicist known as the "father o...
Oppidan
Oppidan refers to an urban dweller or city resident, emphasizing their...
Oppilate
To oppilate means to obstruct or block something, typically a passage ...
Oppo
The opposite of something; contrary or contrasting....
Opponency
Opponency in visual perception refers to the comparison between signal...
Opponent
An opponent is someone who competes against another in a contest or co...
Opportune
The word "opportune" means to take advantage of a favorable situation ...
Opportunism
Opportunism is the practice of taking advantage of opportunities for p...
Opportunist
An opportunist is someone who takes advantage of opportunities for the...
Opportunistic
Opportunistic means taking advantage of opportunities as they arise ra...
Opportunistic infection
Opportunistic infection refers to an infection opportunistic that occu...
Opportunities
Opportunities are chances for growth and progress in various aspects o...
Opportunity
Opportunity is a chance for progress or advancement....
Opportunity cost
The opportunity cost refers to the potential benefits that are foregon...
Opportunity shop
An opportunity shop is a store that sells secondhand items to raise fu...
Opportunity synonym
An opportunity synonym is a chance or opening that allows for potentia...
Opposable
Opposable means being able to oppose or interact with something by bri...
Opposable thumb
An opposable thumb is a thumb that is able to be moved oppositely to t...
Oppose
To oppose means to resist or go against something or someone....
Opposed
Opposed means to be in conflict or resistance to something contrary or...
Opposed-cylinder
Opposed-cylinder refers to an engine design where the cylinders are ar...
Opposed-piston engine
An opposed-piston engine is a type of internal combustion engine where...
Opposeless
Opposeless means having no equal or peer, making someone or something ...
Opposing
Opposing means actively disagreeing or resisting something or someone....
Opposite
The meaning of opposite refers to something that is completely differe...
Opposite field
Opposite field refers to hitting the ball in the opposite direction of...
Opposite number
The term "opposite number" refers to a corresponding counterpart or eq...
Opposite number, one's
An opposite number refers to the corresponding person on the other sid...
Opposite prompt
The meaning of opposite prompt can be understood by focusing on the wo...
Opposite sex
Opposite sex refers to individuals who are of a different gender than ...
Opposition
Opposition is the resistance or disagreement towards a particular idea...
Opposition research
Opposition research involves investigating a political opponent to gat...
Oppositional
Oppositional means being characterized by a tendency to oppose or resi...
Oppositional defiant disorder
Oppositional defiant disorder is a disorder characterized by defiant, ...
Oppositionist
An oppositionist is someone who opposes the current regime or govern...
Oppositive
Opposite means completely different or contrary in nature, form, or ch...
Oppress
To oppress means to suppress or subjugate a group or individual throug...
Oppressed
To be oppressed means to be subject to unjust treatment or control by ...
Oppression
Oppression is the unjust or cruel exercise of authority or power....
Oppressive
Oppressive means unjustly harsh or controlling....
Oppressor
An oppressor is a person or group that exercises power and control ove...
Opprobrious
Opprobrious means disgraceful or shameful behavior that incurs public ...
Opprobrium
Opprobrium is a public disgrace or the harsh criticism or censure of o...
Oppugn
The word oppugn means to contradict or to argue against something....
Oppugnant
Oppugnant means being actively opposed or in conflict with something o...
OPRA
OPRA, or the Open Public Records Act, allows public access to governme...
Opry
Opry is a term that refers to a country music show or venue, especiall...
Ops
"Ops" is a colloquial term referring to operations within a business o...
Opsimath
Opsimath means a person who begins or continues to learn late in life,...
Opsin
"Opsin is a protein found in the retina that plays a crucial role in t...
Opsonic
Opsonic refers to the ability of certain substances to enhance phagocy...
Opsonic index
The opsonic index measures the ability of antibodies to enhance phag...
Opsonify
The meaning of opsonify is to enhance the ability of phagocytic cells ...
Opsonin
An opsonin is a substance that enhances phagocytosis by marking foreig...
Opsonize
Opsonize means to coat a pathogen with antibodies or complement protei...
Opt
The meaning of opt is to make a choice or decision from a range of pos...
Opt in
Opt in means choosing to participate or agree to something, usually by...
Opt out
The meaning of opt out is to choose not to participate or be involved ...
Optative
Optative expresses a wish or hope, often indicated by a verb form endi...
Opted
The term "opted" means to choose or select among different options ava...
Optic
Optic refers to relating to sight or the eyes, with an emphasis on vis...
Optic axis
The optic axis is the imaginary line that runs through the center of a...
Optic chiasma
The optic chiasma is where optic nerves from each eye cross over, allo...
Optic disc
The optic disc is the point on the retina where the optic nerve exits ...
Optic nerve
The optic nerve is the second cranial nerve that transmits visual info...
Optic thalamus
The optic thalamus is a relay station in the brain that processes visu...
Optical
The term optical refers to anything related to sight or vision....
Optical activity
Optical activity refers to the ability of certain substances to rotate...
Optical art
Optical art is an art form that uses optical illusions to create visua...
Optical astronomy
Optical astronomy involves the study of celestial objects using visibl...
Optical bench
An optical bench is a physical platform used for conducting experiment...
Optical binary
Optical binary refers to a system that uses two states of light intens...
Optical center
The optical center is the point on a lens where light rays converge an...
Optical character reader
Optical character reader is a device that can scan printed text and co...
Optical character recognition
Optical character recognition is the automated process of converting t...
Optical computer
An optical computer is a new type of computing technology that uses li...
Optical crown
An optical crown refers to the part of a spectacle lens that is thicke...
Optical density
The optical density refers to the degree of light absorption or transm...
Optical disc
An optical disc is a storage medium that uses a laser to read and writ...