sibilate vs assibilate

sibilate and assibilate both are verbs.

Word	Noun	Adjective	Verb	Adverb
sibilate	No	No	Yes	No
assibilate	No	No	Yes	No

As verbs, assibilate is a hyponym of sibilate; that is, assibilate is a word with a more specific, narrower meaning than sibilate:

sibilate (verb)	assibilate (verb)
make a sharp hissing sound, as if to show disapproval	change into a sibilant
express or utter with a hiss	insert a sibilant sound before or after (another sound)
utter a sibilant
pronounce with an initial sibilant