1. An action or an arrangement that involves two people or groups of people who behave in the same way or agree to help each other and give each other advantages: Sally was impressed with the reciprocation of kindness among her friends.
2. A returning, usually for something given: Mary wanted to invite her neighbor over for lunch as a reciprocation for taking her to the doctor's offie the week before.
3. A mutual giving and receiving: The two sisters thought that the reciprocation of giving each other Christmas presents every year was a great thing.
4. In prosthodontics, the means by which one part of an appliance is made to counter the effect created by another part: Prosthodontics refers to a dental specialty concerned with the restoration and maintenance of oral function by the reciprocation or replacement of missing teeth and structures by artificial devices or prostheses.