unholy vs demonic

unholy and demonic both are adjectives.

Word	Noun	Adjective	Verb	Adverb
unholy	No	Yes	No	No
demonic	No	Yes	No	No

As adjectives, unholy and demonic are synonyms defined as:

unholy and demonic: extremely evil or cruel; expressive of cruelty or befitting hell

Other synonyms of unholy include diabolic, diabolical, fiendish, hellish, infernal, satanic.

unholy (adjective)	demonic (adjective)
not hallowed or consecrated	extremely evil or cruel; expressive of cruelty or befitting hell
extremely evil or cruel; expressive of cruelty or befitting hell
having committed unrighteous acts