reciprocate

verb

1. (transitive)To exchange two things, with both parties giving one thing and taking another thing.

   “The USTR isn't reciprocating actual tariffs. It's just placing the biggest tariffs on the countries running the biggest trade surpluses.”

2. (transitive)To give something else in response (where the "thing" may also be abstract, a feeling or action) To make a reciprocal gift.

   “I gave them apples from my tree; they reciprocated with a pie and some apple jelly.”

   “Nugget appreciates the generosity! Nugget will reciprocate with a Monstermon card!”

3. (intransitive)To move backwards and forwards, like a piston.

   “a reciprocating engine”

   “One brawny smith the puffing bellows plies, / And draws and blows reciprocating air.”

4. (intransitive)To counter, retort or retaliate.