ac·cep·tor / akˈseptər/ • n. a person or thing that accepts something, in particular: ∎  a person or bank that accepts a draft or bill of exchange. ∎  Chem. an atom or molecule that is able to bind to or accept an electron or other species. ∎  Physics such an atom forming a positive hole in a semiconductor.

acceptor
1. (in chemistry) A compound, molecule, ion, etc., to which electrons are donated in the formation of a coordinate bond.

2. (in biochemistry) A receptor that binds a hormone without any apparent biological response.