What is the name of the specific region on an antibody that binds to an antigen?

Explanation

The paratope is the precise site on an antibody that recognizes and attaches to the antigen. Idiotopes are unique antigenic determinants within the variable region of an antibody, epitopes are the antigen parts recognized by antibodies, and haptens are small molecules that elicit an immune response only when attached to a larger carrier.