demon1 /ˈdiːmən/.
Also 6–9 dæmon.
Etymology: In form, and in sense 1 a, a. L. dæmōn (med.L. dēmōn) spirit, evil spirit, a. Gr. δαίμων divinity, genius, tutelary deity. But in sense 1 b and 2, put for L. dæmonium, Gr. δαιμόνιον, neuter of δαιμόνιος adj. ‘(thing) of divine or dæmonic nature or character’, which is used by the LXX, N. Test., and Christian writers, for ‘evil spirit’. Cf. Fr. démon (in Oresme 14th c. démones); also 13th c. demoygne = Pr. demoni, Ital., Sp. demonio, repr. L. dæmonium, Gr. δαιμόνιον.