diabolically

The word's journey begins with the Greek diabolos, meaning "slanderer" or "accuser," derived from the verb diaballein ("to throw across, to slander"). This term was adopted into ecclesiastical Latin as diabolus to denote "the devil," the supreme slanderer against God. The adjective "diabolic" was formed in Late Latin (diabolicus) to mean "devilish," and the English adverbial form "diabolically" emerged by adding the standard adverbial suffix -ally to this adjective. Thus, the literal sense of "in a devilish manner" evolved to describe both profound wickedness and, in informal usage, an extreme degree of something, metaphorically linking supreme evil to supreme intensity.