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iff

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

Definition of iff

  1. :  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

  1. identification, friend or foe




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