As Marcus says, the devil is often in the details in cases like this, “some decimal point in the wrong place.”
Someone who had known her for years told Davies that she could at times seem like “the beating heart of the devil.”
He has kept “the devil way down in the hole,” writes Horspool, by seeming to have done a deal with the angels.
Old English deofol "evil spirit, a devil, the devil, false god, diabolical person," from Late Latin diabolus (also the source of Italian diavolo, French diable, Spanish diablo; German Teufel is Old High German tiufal, from Latin via Gothic diabaulus).
The Late Latin word is from Ecclesiastical Greek diabolos, in Jewish and Christian use, "Devil, Satan" (scriptural loan-translation of Hebrew satan), in general use "accuser, slanderer," from diaballein "to slander, attack," literally "throw across," from dia- "across, through" + ballein "to throw" (see ballistics). Jerome re-introduced Satan in Latin bibles, and English translators have used both in different measures.
In Vulgate, as in Greek, diabolus and dæmon (see demon) were distinct, but they have merged in English and other Germanic languages.
Playful use for "clever rogue" is from c.1600. Meaning "sand spout, dust storm" is from 1835. In U.S. place names, the word often represents a native word such as Algonquian manito, more properly "spirit, god." Phrase a devil way (late 13c.) was originally an emphatic form of away, but taken by late 14c. as an expression of irritation.
Devil's books "playing cards" is from 1729, but the cited quote says they've been called that "time out of mind" (the four of clubs is the devil's bedposts); devil's coach-horse is from 1840, the large rove-beetle, which is defiant when disturbed. "Talk of the Devil, and he's presently at your elbow" [1660s].
(Gr. diabolos), a slanderer, the arch-enemy of man's spiritual interest (Job 1:6; Rev. 2:10; Zech. 3:1). He is called also "the accuser of the brethen" (Rev. 12:10). In Lev. 17:7 the word "devil" is the translation of the Hebrew _sair_, meaning a "goat" or "satyr" (Isa. 13:21; 34:14), alluding to the wood-daemons, the objects of idolatrous worship among the heathen. In Deut. 32:17 and Ps. 106:37 it is the translation of Hebrew _shed_, meaning lord, and idol, regarded by the Jews as a "demon," as the word is rendered in the Revised Version. In the narratives of the Gospels regarding the "casting out of devils" a different Greek word (daimon) is used. In the time of our Lord there were frequent cases of demoniacal possession (Matt. 12:25-30; Mark 5:1-20; Luke 4:35; 10:18, etc.).