giddiness vs lightheadedness

giddiness and lightheadedness both are nouns.

Word	Noun	Adjective	Verb	Adverb
giddiness	Yes	No	No	No
lightheadedness	Yes	No	No	No

As nouns, giddiness and lightheadedness are synonyms defined as:

giddiness and lightheadedness: a reeling sensation; a feeling that you are about to fall

Other synonyms of giddiness include dizziness, vertigo.

giddiness (noun)	lightheadedness (noun)
an impulsive scatterbrained manner	a frivolous lack of prudence
a reeling sensation; a feeling that you are about to fall	a reeling sensation; a feeling that you are about to fall