inverse has 2 distinct synonyms spread across 2 of its 3 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. Its one recorded opposite is direct.
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.
reversed (turned backward) in order or nature or effect
opposite in nature or effect or relation to another quantity
“a term is in inverse proportion to another term if it increases (or decreases) as the other decreases (or increases)”
something inverted in sequence or character or effect
“when the direct approach failed he tried the inverse”
Synonyms, antonyms and the broader and narrower relations for inverse come from Princeton University’s WordNet. Full sources and licences.