airheaded vs featherbrained

airheaded and featherbrained both are adjectives.

Word	Noun	Adjective	Verb	Adverb
airheaded	No	Yes	No	No
featherbrained	No	Yes	No	No

As adjectives, airheaded and featherbrained are synonyms defined as:

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

airheaded (adjective)	featherbrained (adjective)
lacking seriousness; given to frivolity	lacking seriousness; given to frivolity