Definition of -OR (original) (raw)

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

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

: the heraldic color gold or yellow

: 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

2

operational research; operations research

: one that does a (specified) thing

Word History

Etymology

Conjunction (1) and Noun (2)

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

Preposition

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

Noun (1)

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

Noun suffix (1)

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

Noun suffix (2)

Middle English, from Anglo-French, from Latin

First Known Use

Conjunction (1)

13th century, in the meaning defined at sense 1

Preposition

13th century, in the meaning defined above

Conjunction (2)

13th century, in the meaning defined above

Noun (1)

15th century, in the meaning defined above

Noun (2)

1947, in the meaning defined above

Time Traveler

The first known use of or was in the 13th century

Dictionary Entries Near or

Cite this Entry

“Or.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/or. Accessed 14 Feb. 2025.

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Merriam-Webster unabridged