bestial vs beastly

bestial and beastly both are adjectives.

Word	Noun	Adjective	Verb	Adverb
bestial	No	Yes	No	No
beastly	No	Yes	No	Yes

As adjectives, bestial and beastly are synonyms defined as:

bestial and beastly: resembling a beast; showing lack of human sensibility

Other synonyms of bestial include brutal, brute, brutish.

bestial (adjective)	beastly (adjective)
resembling a beast; showing lack of human sensibility	resembling a beast; showing lack of human sensibility
	(informal) very unpleasant

bestial (adverb)	beastly (adverb)
	in a beastly manner