or

play

conjunction \ ər , ˈȯr , Southern also ˈär \

Definition of or

1 —used as a function word to indicate an alternative

coffee or tea

sink or swim

, the equivalent or substitutive character of two words or phrases

lessen or abate

, or approximation or uncertainty

in five or six days

2 archaic :either

3 archaic :whether

4 —used in logic as a sentential connective that forms a complex sentence which is true when at least one of its constituent sentences is true — compare disjunction

Origin and Etymology of or

Middle English, alteration of other, alteration of Old English oththe; akin to Old High German eddo or

NEW! Time Traveler

First Known Use: 13th century

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or

preposition

Definition of or

archaic

:before

Origin and Etymology of or

Middle English, from or, adverb, early, before, from Old Norse ār; akin to Old English ǣr early — more at ere

NEW! Time Traveler

First Known Use: 13th century

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or

conjunction

Definition of or

archaic

:before

First Known Use of or

13th century

or

play

noun \ ˈȯr \

Definition of or

:the heraldic color gold or yellow

Origin and Etymology of or

Middle English, from Anglo-French, gold, from Latin aurum — more at aureus

NEW! Time Traveler

First Known Use: 15th century

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OR

play

noun \ ˈȯr \

Definition of OR

:a logical operator that requires either of two inputs to be present or conditions to be met for an output to be made or a statement to be executed

OR gate in a computer

Origin and Etymology of or

¹or

NEW! Time Traveler

First Known Use: 1940

See Words from the same year

Other Computer-Related Terms

adware, flash, kludge, phishing, recursive, router

OR

abbreviation

Definition of OR

1 operating room

2 operational research; operations research

3 Oregon

4 owner's risk

5 own recognizance

See OR defined for English-language learners

-or

noun suffix

Definition of -or

:one that does a (specified) thing

grantor

Origin and Etymology of -or

Middle English, from Anglo-French -ur, -our, -eour & Latin -or; Anglo-French -ur, -our, from Latin -or; Anglo-French -eour, from Latin -ator, from -a-, verb stem + -tor, agent suffix; akin to Greek -tōr, agent suffix, Sanskrit -tā

-or

noun suffix

Definition of -or

:condition :activity

demeanor

Origin and Etymology of -or

Middle English, from Anglo-French, from Latin

OR Defined for Kids

or

play

conjunction \ ər , ˈȯr \

Definition of or for Students

—used between words or phrases that are choices

juice or milk

Will you leave or stay?

OR

abbreviation

Definition of OR for Students

Oregon

-or

noun suffix \ ər \

Definition of -or for Students

:someone or something that does a specified thing

actor

elevator

-or

noun suffix

Definition of -or for Students

:condition :activity

demeanor

Medical Dictionary

OR

abbreviation

medical Definition of OR

operating room

Law Dictionary

OR

abbreviation

legal Definition of OR

own recognizance

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or

Definition of or

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or

Definition of or

Origin and Etymology of or

or

Definition of or

First Known Use of or

or

Definition of or

Origin and Etymology of or

OR

Definition of OR

Origin and Etymology of or

Other Computer-Related Terms

OR

Definition of OR

-or

Definition of -or

Origin and Etymology of -or

-or

Definition of -or

Origin and Etymology of -or

OR Defined for Kids

or

Definition of or for Students

OR

Definition of OR for Students

-or

Definition of -or for Students

-or

Definition of -or for Students

Medical Dictionary

OR

medical Definition of OR

Law Dictionary

OR

legal Definition of OR

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