build has 22 distinct synonyms spread across 6 of its 12 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.
improve the cleansing action of
“build detergents”
order, supervise, or finance the construction of
“The government is building new schools in this state”
give form to, according to a plan
“build a modern nation”
be engaged in building
“These architects build in interesting and new styles”
found or ground
“build a defense on nothing but the accused person's reputation”
develop and grow
“Suspense was building right from the beginning of the opera”
Synonyms, antonyms and the broader and narrower relations for build come from Princeton University’s WordNet. Full sources and licences.