Dictionary

iff

conjunction \ˈif-ən(d)-ˈōn-lē-ˌif; ˈif, sometimes read with a prolonged f\

Definition of IFF

:  if and only if <two figures are congruent iff one can be placed over the other so that they coincide>

Origin of IFF

alteration of 1if
First Known Use: 1955

IFF

abbreviation

Definition of IFF

identification, friend or foe

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