if and only if

/ɪf ən(d)ˈoʊn.li ɪf/

Word Rarity Common

Frequency: Zipf frequency 5.83 in modern English

Scrabble Score

Letters

Syllables

Unique Chars

Meaning

conj

Is equivalent to; implies and is implied by; is true and false in the same cases as.

conj

Informal

"A rectangle is a square if and only if all four of its sides have the same length."
"An integer is even if and only if its square is also even."
"I'll let you go to the concert if and only if you clean your room."

if and when only if when and only when

if if and when iff only if when and only when ↔ ⇔

iff

Questions

How do you pronounce if and only if?

The recorded pronunciation is /ɪf ən(d)ˈoʊn.li ɪf/.

What does if and only if mean?

Is equivalent to; implies and is implied by; is true and false in the same cases as.

How to pronounce if and only if

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