rocket has 9 distinct synonyms spread across 6 of its 7 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.
a jet engine containing its own propellant and driven by reaction propulsion
erect European annual often grown as a salad crop to be harvested when young and tender
propels bright light high in the sky, or used to propel a lifesaving line or harpoon
Synonyms, antonyms and the broader and narrower relations for rocket come from Princeton University’s WordNet. Full sources and licences.