inversion has 5 distinct synonyms spread across 4 of its 9 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.
the layer of air near the earth is cooler than an overlying layer
abnormal condition in which an organ is turned inward or inside out (as when the upper part of the uterus is pulled into the cervical canal after childbirth)
Synonyms, antonyms and the broader and narrower relations for inversion come from Princeton University’s WordNet. Full sources and licences.
a chemical process in which the direction of optical rotation of a substance is reversed from dextrorotatory to levorotary or vice versa
(genetics) a kind of mutation in which the order of the genes in a section of a chromosome is reversed
(counterpoint) a variation of a melody or part in which ascending intervals are replaced by descending intervals and vice versa
a term formerly used to mean taking on the gender role of the opposite sex