coupling, mating, pairing, conjugation, union, sexual union -- (the act of pairing a male and female for reproductive purposes; "the casual couplings of adolescents"; "the mating of some species occurs only in the spring")
Overview of verb mate
The verb mate has 3 senses
copulate, mate, pair, couple -- (engage in sexual intercourse; "Birds mate in the Spring")
match, mate, couple, pair, twin -- (bring two objects, ideas, or people together; "This fact is coupled to the other one"; "Matchmaker, can you match my daughter with a nice young man?"; "The student was paired with a partner for collaboration on the project")
checkmate, mate -- (place an opponent's king under an attack from which it cannot escape and thus ending the game; "Kasparov checkmated his opponent after only a few moves")