cuckoo in German

Any of various birds, of the family Cuculidae within the order Cuculiformes, famous for laying its eggs in the nests of other species; but especially a common cuckoo (Cuculus canorus), that has a characteristic two-note call.

The sound of that particular bird.

A person who inveigles themselves into a place where they should not be (used especially in the phrase a cuckoo in the nest).