To endure against; stand or ward off; defend against; withstand; resist.
To offset; compensate for; make restitution for.
Offset; restitution.
To counter, retort or retaliate.
To move backwards and forwards, like a piston.
To exchange two things, with both parties giving one thing and taking another thing.
To give something else in response (where the "thing" may also be abstract, a feeling or action) To make a reciprocal gift.