loaf sugar vs loaf

loaf sugar and loaf both are nouns.

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

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

Other hypernyms of loaf sugar include refined sugar, sugar.

loaf sugar (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

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