whiff has 3 distinct synonyms spread across 3 of its 8 senses. Each sense below keeps its own list, because a synonym belongs to a meaning and not to a word: swapping one sense's substitute into another sense's sentence is how a thesaurus makes writing worse. WordNet records no antonym for it — antonymy is a relation between word forms rather than concepts, so it is deliberately sparse.
Counts are distinct word forms across every sense. A synonym that appears under three senses is counted once here and shown three times below, under each sense it belongs to.
drive or carry as if by a puff of air
“The gust of air whiffed away the clouds”
Synonyms, antonyms and the broader and narrower relations for whiff come from Princeton University’s WordNet. Full sources and licences.
strike out by swinging and missing the pitch charged as the third
utter with a puff of air
“whiff out a prayer”
a lefteye flounder found in coastal waters from New England to Brazil
a strikeout resulting from the batter swinging at and missing the ball for the third strike