4
crackpot(adjective, impractical, half-baked, doomed)
4
credulous(adjective, foolish, stupid, innocent, green)
4
demented(adjective, wrong, wild, foolish, stupid)
4
gaga(adjective, ability, informal)
4
green(adjective, foolish, stupid, innocent, thick)
4
heedless(adjective, careless, foolish, crazy, senseless)
4
ignoramus(noun, simple, fool, innocent, jerk)
4
incongruous(adjective, foolish, stupid, insignificant, unreasonable)
4
inconsequential(adjective, wrong, slight, small, foolish)
4
injudicious(adjective, weak, simple, careless, foolish)
4
jejune(adjective, dull, soft, slight, flat)
4
lightheaded
4
loco
4
loopy(adjective, knowledge, ability, informal, foolish)
4
madcap(adjective, careless, foolish, crazy, vague)
4
muzzy
4
nitwit(noun, simple, fool, innocent, jerk)
4
potty(adjective, wild, foolish, stupid, crazy)
4
rattlebrained
4
stunned
10 years ago|39k views|share |citing 
APASmart Define. (2016). silly thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/silly/thesaurus/synonyms
ChicagoSmart Define. 2016. "silly thesaurus" https://smartdefine.org/silly/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2016, silly thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/silly/thesaurus/synonyms>.
MLASmart Define. "silly thesaurus" 20 January 2016. Web. 21 September 2026. <https://smartdefine.org/silly/thesaurus/synonyms>