diabolical vs demonic

diabolical and demonic both are adjectives.

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

As adjectives, diabolical and demonic are synonyms defined as:

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

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

diabolical (adjective)	demonic (adjective)
extremely evil or cruel; expressive of cruelty or befitting hell	extremely evil or cruel; expressive of cruelty or befitting hell
showing the cunning or ingenuity or wickedness typical of a devil