Fiend \Fiend\, n. [OE. fend, find, fiend, feond, fiend, foe, AS. fe['o]nd; akin to OS. f[=i]ond, D. vijand enemy, OHG. f[=i]ant, G. feind, Icel. fj[=a]nd, Sw. & Dan. fiende, Goth. fijands; orig. p. pr. of a verb meaning to hate, AS. fe['o]n, fe['o]gan, OHG. f[=i]?n, Goth. fijan, Skr. p[=i]y to scorn;

1. Cf. Foe, Friend.]

An implacable or malicious foe; one who is diabolically wicked or cruel; an infernal being; -- applied specifically to the devil or a demon.

Into this wild abyss the wary fiend Stood on the brink of Hell and looked a while. --Milton.

O woman! woman! when to ill thy mind Is bent, all hell contains no fouler fiend. --Pope.

Source: Webster's Revised Unabridged Dictionary (1913)