nutty as a fruitcake

(as) nutty as a fruitcake

Crazy or wacky. Usually used humorously. The kids are always nutty as fruitcakes when they've had something sugary to eat. My Aunt Jeannie has always been nutty as a fruitcake.
See also: fruitcake, nutty
Farlex Dictionary of Idioms.

*nutty as a fruitcake

 and nuttier than a fruitcake
crazy. (*Also: as ~.) Don't pay any attention to John; he's nutty as a fruitcake. Mary's schemes for making money are nuttier than a fruitcake.
See also: fruitcake, nutty
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

nutty as a fruitcake

Crazy, idiotic, as in Mary's nutty as a fruitcake if she thinks she can get away with that. The adjective nutty meaning "insane" was first recorded in 1821; the similarity to fruitcake, which literally contains nuts as well as fruit, was first recorded in 1935.
See also: fruitcake, nutty
The American Heritage® Dictionary of Idioms by Christine Ammer.

nutty as a fruitcake

BRITISH, INFORMAL
If someone is as nutty as a fruitcake, they are crazy. The man is a charmer — intense, funny, and nutty as a fruitcake. Note: `Nutty' or `nuts' is an informal word for mad. Nutty can also mean containing a lot of nuts in the way that a fruitcake often does.
See also: fruitcake, nutty
Collins COBUILD Idioms Dictionary, 3rd ed.

nutty as a fruitcake

completely crazy. informal
Nutty meaning ‘mad or crazy’ dates from the late 19th century, and this phrase, punning on the sense of ‘full of nuts’, from the 1930s. Fruitcake is also used on its own to mean ‘a crazy or eccentric person’.
See also: fruitcake, nutty
Farlex Partner Idioms Dictionary

(as) nutty as a ˈfruitcake

(informal, humorous) (of a person) completely crazy: He’s as nutty as a fruitcake. Do you know what he did yesterday? He had lunch outside in the pouring rain.
See also: fruitcake, nutty
Farlex Partner Idioms Dictionary

nutty as a fruitcake

verb
See as nutty as a fruitcake
See also: fruitcake, nutty
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • as nutty as a fruitcake
  • fruitcake
  • (as) nutty as a fruitcake
  • nutty
  • nuttier than a fruitcake
  • here/there (one) goes again
  • never a dull moment
  • as always
  • it was ever so
  • twa