cuckoo

adj. acting in a way that is crazy, strange, or very silly.

adj. mentally unbalanced or eccentric. Used as a predicative adjective in informal contexts.

“You must be cuckoo if you think I am going to jump into that freezing water.”

“The neighbors thought the old man had gone completely cuckoo when he started painting his entire house bright purple in the middle of the night.”

Informal · Slang

n. a grey bird that makes a famous two-note sound and lays its eggs in other birds' nests.

n. any bird of the family Cuculidae, noted for its characteristic call and brood parasitism.

“We heard a cuckoo calling from the woods early this morning.”

“The common cuckoo is famous for its parasitic behavior, laying its eggs in the nests of smaller songbirds to be raised by unsuspecting foster parents.”

n. a person who is acting crazy or strange.

n. a person perceived as insane or highly eccentric.

“Don't listen to him; he's just a bit of a cuckoo.”

“The local kids whispered that the hermit was a total cuckoo, though he was actually just a retired professor who enjoyed his privacy.”

Informal · Slang

v. to say the same thing over and over again in an annoying way.

v. to repeat a statement or idea incessantly, mimicking the repetitive nature of the bird's call.

“He kept cuckooing the same political slogans all evening.”

“The critics cuckooed the same tired complaints about the director's style without offering any fresh analysis of the film itself.”

Literary

v. when criminals take over a vulnerable person's home to use it for illegal activities.

v. to take over the residence of a vulnerable individual to use it as a base for drug dealing or other criminal activity.

“The police are trying to protect elderly residents from being cuckooed by local gangs.”

“Authorities have seen a rise in cuckooing, where organized crime groups exploit vulnerable tenants to establish safe houses for distribution.”

British English · Technical