diabolˈical adjective (informal)

1. Very shocking, annoying or difficult
2. Outrageous
3. Very bad, unpleasant
4. (as an intensifier) complete or absolute

diabolˈically adverb

diabˈolism noun

1. Devil-worship
2. Devilry

diabˈolist noun

A person knowledgeable on diabolism

diabolize or diabolise /-abˈə-līz/ transitive verb

To make devilish

diabolˈogy or diabololˈogy noun

1. The doctrine of devils
2. Devil-lore