reciprocal

Hybridization involving a pair of crosses that reverse the sexes associated with each genotype.

(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.

Something (a term or expression or concept) that has an inverse relation to something else.

“risk is the reciprocal of safety”

Concerning each of two or more persons or things; especially given or done in return.

“reciprocal aid”

“reciprocal trade”

Of or relating to the multiplicative inverse of a quantity or function.

“the reciprocal ratio of a:b is b:a”