luffa has 7 distinct synonyms spread across 2 of its 2 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.
the dried fibrous part of the fruit of a plant of the genus Luffa; used as a washing sponge or strainer
any of several tropical annual climbers having large yellow flowers and edible young fruits; grown commercially for the mature fruit's dried fibrous interior that is used as a sponge
Synonyms, antonyms and the broader and narrower relations for luffa come from Princeton University’s WordNet. Full sources and licences.