jerk has 12 distinct synonyms spread across 9 of its 11 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.
(mechanics) the rate of change of acceleration
meat (especially beef) cut in strips and dried in the sun
raising a weight from shoulder height to above the head by straightening the arms
Synonyms, antonyms and the broader and narrower relations for jerk come from Princeton University’s WordNet. Full sources and licences.
make an uncontrolled, short, jerky motion
“his face is twitching”