Reciprocal
/ɹɪˈsɪpɹək(ə)l/
noun
The number obtained by dividing 1 by another given number; the result of exchanging the numerator and the denominator of a fraction.
“0.5 is the reciprocal of 2.”
(grammar) A construction expressing mutual action.
Synonyms: multiplicative inverse
adjective
Of a feeling, action or such: mutual, uniformly felt or done by each party towards the other or others; two-way.
“reciprocal love; reciprocal duties”
Mutually interchangeable.
(grammar) expressing mutual action, applied to pronouns and verbs; also in a broad sense: reflexive
Synonyms: reflexive, contrary, converse, cross, inverse, inverted, opposite, mutual