iff

¹

Mathematics.

1. if and only if.

IFF

²

Military.

1. Identification, Friend or Foe: a system of transmitters and transponders that uses coded signals to distinguish between friendly and hostile aircraft.

IFF

¹

abbreviation for

1. Identification, Friend or Foe: a system using radar transmissions to which equipment carried by friendly forces automatically responds with a precoded signal

iff

²

/ ɪf /

conjunction

1. 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

Example Sentences

The IFF, however, is not exactly an organization to be proud of.

From The Daily Beast

It was a kind of stick called vahs-iff, which did not grow there, therefore they had not been able to find it.

From Project Gutenberg

It would more encurrege to wed, iff so be one know'd it before-hand, as one may say.

From Project Gutenberg

The IFF mechanism reconverts our beam to a predetermined pulse, and it bounces back to us in a different pattern.

From Project Gutenberg

And what wold ye doe with my bryde soe gay, Iff I did sell her thee?

From Project Gutenberg

Now while Staff was receiving this impression, Mr. Iff looked sharply round; their glances crossed.

From Project Gutenberg