sizz vs utter

sizz is not an adjective while utter is an adjective.

Word	Noun	Adjective	Verb	Adverb
sizz	No	No	Yes	No
utter	No	Yes	Yes	No

As verbs, utter is a hypernym of sizz; that is, utter is a word with a broader meaning than sizz:

Other hypernyms of sizz include emit, let loose, let out.

As verbs, utter is a hypernym of sizz; that is, utter is a word with a broader meaning than sizz:

Other hypernyms of sizz include mouth, speak, talk, verbalise, verbalize.

sizz (adjective)	utter (adjective)
	complete and absolute
	without qualification; used informally as (often pejorative) intensifiers

sizz (verb)	utter (verb)
make a sharp hissing sound, as if to show disapproval	express in speech
express or utter with a hiss	articulate; either verbally or with a cry, shout, or noise
	express audibly; utter sounds (not necessarily words)
	put into circulation