Reciprocal

1. Of a feeling, action or such: mutual, uniformly felt or done by each party towards the other or others; two-way.
2. Mutually interchangeable.
3. (grammar) expressing mutual action, applied to pronouns and verbs; also in a broad sense: reflexive
4. (mathematics) Used to denote different kinds of mutual relation; often with reference to the substitution of reciprocals for given quantities.
5. Done, given, felt, or owed in return

Synonyms

• mutual, two-way
• contrary, opposite, converse, inverse, inverted, cross
• (grammar): reflexive