ice pack vs ice

ice pack and ice both are nouns.

Word	Noun	Adjective	Verb	Adverb
ice pack	Yes	No	No	No
ice	Yes	No	Yes	No

As nouns, ice is a hypernym of ice pack; that is, ice is a word with a broader meaning than ice pack:

ice pack (noun)	ice (noun)
a waterproof bag filled with ice: applied to the body (especially the head) to cool or reduce swelling	a rink with a floor of ice for ice hockey or ice skating
a large expanse of floating ice	an amphetamine derivative (trade name Methedrine) used in the form of a crystalline hydrochloride; used as a stimulant to the nervous system and as an appetite suppressant
	a frozen dessert with fruit flavoring (especially one containing no milk)
	a flavored sugar topping used to coat and decorate cakes
	the frozen part of a body of water
	diamonds
	water frozen in the solid state