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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

: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

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Origin and Etymology of iff

alteration of 1if

IFF

abbreviation

Definition of IFF

identification, friend or foe

Learn More about iff

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