Meaning & use
Iff
Last updated
If and only if; used in mathematics and logic to indicate that two statements are logically equivalent.
See it in a sentence
A number is even iff it is divisible by two.
The theorem holds iff both conditions are satisfied simultaneously.
A note on using this word
'Iff' is a deliberate shorthand invented by mathematicians and logicians to make biconditional statements easier to write and read.
Words with a similar meaning
if and only if
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