/ ɪf; NAmE / conjunction
( mathematics ) an expression used in mathematics to mean 'if and only if'
••
WORD ORIGIN
1950s: arbitrary extension of if .
/ ɪf; NAmE / conjunction
( mathematics ) an expression used in mathematics to mean 'if and only if'
••
WORD ORIGIN
1950s: arbitrary extension of if .
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005