rudeness vs crust

rudeness and crust both are nouns.

Word	Noun	Adjective	Verb	Adverb
rudeness	Yes	No	No	No
crust	Yes	No	Yes	No

As nouns, crust is a hyponym of rudeness; that is, crust is a word with a more specific, narrower meaning than rudeness:

rudeness (noun)	crust (noun)
a manner that is rude and insulting	the trait of being rude and impertinent; inclined to take liberties
a wild or unrefined state	the outer layer of the Earth
	a hard outer layer that covers something

rudeness (verb)	crust (verb)
	form a crust or form into a crust