light-headed vs lightheaded

light-headed and lightheaded both are adjectives.

Word	Noun	Adjective	Verb	Adverb
light-headed	No	Yes	No	No
lightheaded	No	Yes	No	No

As adjectives, light-headed and lightheaded are synonyms defined as:

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

As adjectives, light-headed and lightheaded are synonyms defined as:

Other synonyms of light-headed include faint, light, swooning.

light-headed (adjective)	lightheaded (adjective)
lacking seriousness; given to frivolity	lacking seriousness; given to frivolity
weak and likely to lose consciousness	weak and likely to lose consciousness