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
used in logic and mathematics

Origin and Etymology of iff

alteration of 1if


IFF

abbreviation

Definition of IFF

identification, friend or foe

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