iff

See also: IFF

English

Pronunciation

• Read as “if and only if”

Conjunction

iff

1. (mathematics, logic) If and only if; used to show that the truth values of two statements are the same.
2. (mathematics, logic) logically equivalent to rephrases:

   A rectangle is a square iff all four of its sides have the same length.

   1. biconditionally
   2. just in case or just in the case that
   3. equal
   4. that is to say
   5. XNOR
3. Obsolete spelling of if.

Related terms

• if
• implies
• not
• and
• or
• xor
• nand
• nor

See also

• formal logic

Translations

abbreviation of if and only if

• Danish: hviss
• Dutch: desda
• Finnish: joss (fi)
• French: ssi (fr)
• German: gdw.
• Hebrew: אםם‎ (he)
• Hungarian: acsa

• Norwegian: hviss (no)
• Polish: wtw
• Portuguese: sse, sss
• Romanian: ddacă
• Russian: титтк (tittk)
• Spanish: sii
• Swedish: omm (sv)

Anagrams

• FFI, FIF, Fif.