reciprocal has 3 distinct synonyms spread across 3 of its 5 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 nonreciprocal.
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.
something (a term or expression or concept) that has an inverse relation to something else
“risk is the reciprocal of safety”
(mathematics) one of a pair of numbers whose product is 1: the reciprocal of 2/3 is 3/2; the multiplicative inverse of 7 is 1/7
1 of the 5 recorded senses carries no synonym, antonym or related term, so it is not shown above. Every sense, with its definition and examples, is on the full entry for reciprocal.
Synonyms, antonyms and the broader and narrower relations for reciprocal come from Princeton University’s WordNet. Full sources and licences.
hybridization involving a pair of crosses that reverse the sexes associated with each genotype
concerning each of two or more persons or things; especially given or done in return
“reciprocal aid”