'Simpleton' definitions:

Definition of 'simpleton'

From: WordNet
noun
A person lacking intelligence or common sense [syn: simpleton, simple]

Definition of 'Simpleton'

From: GCIDE
  • Simpleton \Sim"ple*ton\, n. [Cf. F. simplet, It. semplicione.] A person of weak intellect; a silly person. [1913 Webster]

Synonyms of 'simpleton'

From: Moby Thesaurus