Synonyms for Simpleton:

n.

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

Other synonyms:

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

Usage examples for simpleton

  1. There's not time; and I 'm a simpleton at the game. – The Complete Project Gutenberg Works of George Meredith by George Meredith
  2. If your philosophy can find no answer to the question, will you expect a hopeless simpleton to furnish one? – The Children of the World by Paul Heyse