Definition of "iff"
conjunction:
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If and only if; used to show that the predicate that follows it has the same truth value as the predicate that precedes it.
from Wiktionary, Creative Commons Attribution/Share-Alike License
-
If and only if; used to show that the predicate that follows it has the same truth value as the predicate that precedes it.
from Wiktionary, Creative Commons Attribution/Share-Alike License