airheaded vs empty-headed

airheaded and empty-headed both are adjectives.

Word	Noun	Adjective	Verb	Adverb
airheaded	No	Yes	No	No
empty-headed	No	Yes	No	No

As adjectives, airheaded and empty-headed are synonyms defined as:

Other synonyms of airheaded include dizzy, featherbrained, giddy, light-headed, lightheaded, silly.

airheaded (adjective)	empty-headed (adjective)
lacking seriousness; given to frivolity	lacking seriousness; given to frivolity