Synonyms for Nincompoop:

n.

clown, joker, maniac, dumb blond, numpty. ability, ding-dong, dip, gander, goof, goose, jerk, nerd, schmuck, simple, tomfool, turkey, Mooncalf, schmo, softhead. fool (noun)
blockhead, bonehead, bungler, clod, cretin, dimwit, dolt, dullard, dumbbell, dummy, dunce, fool, half-wit, ignoramus, imbecile, loon, moron, nitwit, simpleton, crackpot, chuckle-head, knuckle-head, lame-brain, meathead.
idiot (noun)
blockhead, clod, dolt, fool, imbecile, jerk, moron, ninny, nitwit, simpleton.
nincompoop (noun)
ninny.
person (noun)
ninny.
schmuck (noun)
schmuck.
stupid person (noun)
dunce.

Other synonyms:

ding-dong, nerd, schmuck, tomfool, schmo, softhead. goof, goose, turkey, Mooncalf. gander. simple. Other relevant words:
ability, clown, ding-dong, dip, gander, goof, goose, jerk, joker, maniac, nerd, ninny, schmuck, simple, tomfool, turkey, Mooncalf, schmo, softhead, numpty.

Usage examples for nincompoop

  1. " Oh, I'm not such a nincompoop as you might suspect, madam," said I, testily, far from complimented. – A Fool and His Money by George Barr McCutcheon
  2. If he hinted that a certain new comer impressed him unfavorably, the nincompoop was summarily kicked out of society. – Hoosier Mosaics by Maurice Thompson
  3. But Rachel, though she is inclined to be tyrannical, is not such a downright positive old blue- bottle nincompoop as that white- wigged king of kings. – The Landleaguers by Anthony Trollope