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Definitions

knucklehead

[nuhk-uhl-hed] / ˈnʌk əlˌhɛd /
NOUN
blockhead
Synonyms
STRONGEST
dummy
STRONG
bonehead chump dolt dunce fool idiot jackass moron nincompoop ninny noodle numskull oaf simpleton tomfool
WEAK
beefhead clodpoll halfwit hardhead harebrain
Antonyms
STRONG
brain genius
NOUN
dumbo
Synonyms
WEAK
blockhead clod dodo dolt dullard dumbbell dummkopf dunce fool halfwit idiot ignoramus imbecile knothead moron nitwit numskull oaf simpleton
NOUN
dunce
Synonyms
STRONGEST
clodpoll
STRONG
ass birdbrain blockhead bonehead buffoon dimwit dolt donkey dope dork dullard dunderhead fool goof half-wit idiot ignoramus imbecile jerk lightweight moron nincompoop ninny nitwit numskull oaf pinhead scatterbrain schnook simpleton twit
WEAK
goof ball lame-brain
Antonyms
STRONG
brain genius

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.