diabolical vs hellish

diabolical and hellish both are adjectives.

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

As adjectives, diabolical and hellish are synonyms defined as:

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

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

diabolical (adjective)	hellish (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	(informal) very unpleasant