sugar loaf vs loaf

sugar loaf and loaf both are nouns.

Word	Noun	Adjective	Verb	Adverb
sugar loaf	Yes	No	No	No
loaf	Yes	No	Yes	No

As nouns, loaf is a hypernym of sugar loaf; that is, loaf is a word with a broader meaning than sugar loaf:

Other hypernyms of sugar loaf include refined sugar, sugar.

sugar loaf (noun)	loaf (noun)
a large conical loaf of concentrated refined sugar	a shaped mass of baked bread that is usually sliced before eating
	a quantity of food (other than bread) formed in a particular shape

sugar loaf (verb)	loaf (verb)
	be about a place without any apparent purpose
	be lazy or idle