mix in vs mix

mix in is not a noun while mix is a noun.

Word	Noun	Adjective	Verb	Adverb
mix in	No	No	Yes	No
mix	Yes	No	Yes	No

As verbs, mix is a hypernym of mix in; that is, mix is a word with a broader meaning than mix in:

Other hypernyms of mix in include blend, coalesce, combine, commingle, conflate, flux, fuse, immix, meld, merge.

As verbs, mix in and mix are synonyms defined as:

mix in (noun)	mix (noun)
	the act of mixing together
	an event that combines things in a mixture
	a commercially prepared mixture of dry ingredients

mix in (verb)	mix (verb)
cause (something) to be mixed with (something else)	mix together different elements
add as an additional element or part	add as an additional element or part
	combine (electronic signals)
	to bring or combine together or with something else
	mix so as to make a random order or arrangement
	open (a place) to members of all races and ethnic groups