boneheaded vs thickheaded

boneheaded and thickheaded both are adjectives.

Word	Noun	Adjective	Verb	Adverb
boneheaded	No	Yes	No	No
thickheaded	No	Yes	No	No

As adjectives, boneheaded and thickheaded are synonyms defined as:

Other synonyms of boneheaded include blockheaded, duncical, duncish, fatheaded, loggerheaded, thick-skulled, thick, wooden-headed.

boneheaded (adjective)	thickheaded (adjective)
(used informally) stupid	(used informally) stupid