Akademik

diabolic
adj. (also diabolical)
1 of the Devil.
2 devilish; inhumanly cruel or wicked.
3 fiendishly clever or cunning or annoying.
Derivatives:
diabolically adv.
Etymology: ME f. OF diabolique or LL diabolicus f. L diabolus (as DEVIL)

Useful english dictionary. 2012.