stage fright vs fearfulness

stage fright and fearfulness both are nouns.

Word	Noun	Adjective	Verb	Adverb
stage fright	Yes	No	No	No
fearfulness	Yes	No	No	No

As nouns, fearfulness is a hypernym of stage fright; that is, fearfulness is a word with a broader meaning than stage fright:

stage fright: fear that affects a person about to face an audience
fearfulness: an emotion experienced in anticipation of some specific pain or danger (usually accompanied by a desire to flee or fight)

Other hypernyms of stage fright include fear, fright.

stage fright (noun)	fearfulness (noun)
fear that affects a person about to face an audience	the trait of being afraid
	an emotion experienced in anticipation of some specific pain or danger (usually accompanied by a desire to flee or fight)