egg yolk vs fixings

egg yolk and fixings both are nouns.

Word	Noun	Adjective	Verb	Adverb
egg yolk	Yes	No	No	No
fixings	Yes	No	No	No

As nouns, fixings is a hypernym of egg yolk; that is, fixings is a word with a broader meaning than egg yolk:

egg yolk: the yellow spherical part of an egg that is surrounded by the albumen
fixings: food that is a component of a mixture in cooking

Other hypernyms of egg yolk include ingredient.

egg yolk (noun)	fixings (noun)
the yellow spherical part of an egg that is surrounded by the albumen	the accessories that normally accompany (something or some activity)
	food that is a component of a mixture in cooking