patch has 17 distinct synonyms spread across 10 of its 13 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 small area of ground covered by specific vegetation
“a bean plot”
a piece of cloth used as decoration or to mend or cover a hole
a short set of commands to correct a bug in a computer program
a connection intended to be used for a limited time
a piece of soft material that covers and protects an injured part of the body
provide with a patch; also used metaphorically
“The field was patched with snow”
Synonyms, antonyms and the broader and narrower relations for patch come from Princeton University’s WordNet. Full sources and licences.