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Definition of or
(Entry 1 of 8)
1 —used as a function word to indicate an alternativecoffee or teasink or swim , the equivalent or substitutive character of two words or phraseslessen or abate , or approximation or uncertaintyin 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
or
prepositionDefinition of or (Entry 2 of 8)
archaic
: before
Definition of or (Entry 3 of 8)
archaic
: before
or
noun (1)Definition of or (Entry 4 of 8)
: the heraldic color gold or yellow
OR
noun (2)Definition of OR (Entry 5 of 8)
: 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
OR
abbreviationDefinition of OR (Entry 6 of 8)
1 operating room
2 operational research; operations research
3 Oregon
4 owner's risk
5 own recognizance
-or
noun suffix (1)Definition of -or (Entry 7 of 8)
: one that does a (specified) thing grantor
-or
noun suffix (2)Definition of -or (Entry 8 of 8)
: condition : activity demeanor
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A More Exception(al) Quiz
- Which of the following words is not a synonym for ‘a young person’?
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Can you spell these 10 commonly misspelled words?
TAKE THE QUIZ
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Merriam-Webster unabridgedWords at Play
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Time Traveler for or
The first known use of or was in the 13th century
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