or

conjunction \ ər , ˈȯr , Southern also ˈär \

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

in the meaning defined at sense 1

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or

preposition

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

in the meaning defined above

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or

conjunction

archaic

: before

First Known Use of or

13th century

in the meaning defined above

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or

noun \ ˈȯr \

: 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

in the meaning defined above

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OR

noun \ ˈȯr \

: a logical operator that requires at least one 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: 1947

in the meaning defined above

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Other Computer-Related Terms

adware, flash, kludge, phishing, recursive, router

OR

abbreviation

1 operating room

2 operational research; operations research

3 Oregon

4 owner's risk

5 own recognizance

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-or

noun suffix

: 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