bonito has 2 distinct synonyms spread across 1 of its 3 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.
flesh of mostly Pacific food fishes of the genus Sarda of the family Scombridae; related to but smaller than tuna
fish whose flesh is dried and flaked for Japanese cookery; may be same species as skipjack tuna
Synonyms, antonyms and the broader and narrower relations for bonito come from Princeton University’s WordNet. Full sources and licences.
any of various scombroid fishes intermediate in size and characteristics between mackerels and tunas