share has 13 distinct synonyms spread across 6 of its 10 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.
assets belonging to or due to or contributed by an individual person or group
“he wanted his share in cash”
any of the equal portions into which the capital stock of a corporation is divided and ownership of which is evidenced by a stock certificate
“he bought 100 shares of IBM at the market price”
the effort contributed by a person in bringing about a result
“I am proud of my contribution in advancing the project”
a sharp steel wedge that cuts loose the top layer of soil
use jointly or in common
Synonyms, antonyms and the broader and narrower relations for share come from Princeton University’s WordNet. Full sources and licences.
communicate
“I'd like to share this idea with you”