n. [ OE. fend, find, fiend, feond, fiend, foe, AS. feónd; akin to OS. fīond, D. vijand enemy, OHG. fīant, G. feind, Icel. fjānd, Sw. & Dan. fiende, Goth. fijands; orig. p. pr. of a verb meaning to hate, AS. feón, feógan, OHG. fī&unr_;n, Goth. fijan, Skr. pīy to scorn; prob. akin to E. feud a quarrel. √81. 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. [ 1913 Webster ]

Into this wild abyss the wary fiend
Stood on the brink of Hell and looked a while. Milton. [ 1913 Webster ]

O woman! woman! when to ill thy mind
Is bent, all hell contains no fouler fiend. Pope. [ 1913 Webster ]

a. Full of fiendish spirit or arts. Marlowe.

-- Fiend"ful*ly, adv. [1913 Webster]

a. Like a fiend; diabolically wicked or cruel; infernal; malignant; devilish; hellish. -- Fiend"ish*ly, adv. -- Fiend"ish*ness, n. [ 1913 Webster ]

a. Fiendish; diabolical. Longfellow. [ 1913 Webster ]

a. [ AS. feóndlic. ] Fiendlike; monstrous; devilish. [ Obs. ] Chaucer. [ 1913 Webster ]