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iff
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Mathematics.
if and only if.
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Words nearby iff
Other definitions for iff (2 of 2)
IFF
Military.
Identification, Friend or Foe: a system of transmitters and transponders that uses coded signals to distinguish between friendly and hostile aircraft.
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Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
How to use iff in a sentence
British Dictionary definitions for iff (1 of 2)
iff
/ (ɪf) /
conjunction
logic a shortened form of if and only if : it indicates that the two sentences so connected are necessary and sufficient conditions for one another. Usually iff is used for equivalence in the metalanguage, rather than as the biconditional in the object language
British Dictionary definitions for iff (2 of 2)
IFF
/ military /
abbreviation for
Identification, Friend or Foe: a system using radar transmissions to which equipment carried by friendly forces automatically responds with a precoded signal
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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