churn vs roil

churn is a noun but roil is not a noun.

Word	Noun	Adjective	Verb	Adverb
churn	Yes	No	Yes	No
roil	No	No	Yes	No

As verbs, churn and roil are synonyms defined as:

Other synonyms of churn include boil, moil.

churn (noun)	roil (noun)
a vessel in which cream is agitated to separate butterfat from buttermilk

churn (verb)	roil (verb)
stir (cream) vigorously in order to make butter	make turbid by stirring up the sediments of
be agitated	be agitated