[iff] conj [alter. of [1]if] (1955): if and only if "two figures are congruent ~ one can be placed over the other so that they coincide"
IFF
Meaning of IFF in English
Merriam-Webster English vocab. Английский словарь Merriam Webster. 2012
[iff] conj [alter. of [1]if] (1955): if and only if "two figures are congruent ~ one can be placed over the other so that they coincide"
Merriam-Webster English vocab. Английский словарь Merriam Webster. 2012