Emily Dickinson Lexicon

DE'MON, n. [L. dæmon; Gr. δαιμων; Sp. It. demonio; Fr. demon; Ir. deamal or deamon. The origin and primary sense of this word I have not been able to ascertain. Qu. Ar. دَهِمَ dahima, daima, to fall suddenly, to rush, to overwhelm, to obscure, to blacken; whence misfortune, black, blackness, evil, a monster: or is it a compound of dea, dia, deus, and mon, a word signifying evil, from the Persian? I place little confidence in these conjectures.]

A spirit, or immaterial being, holding a middle place between men and the celestial deities of the Pagans. The ancients believed that there were good and evil demons, which had influence over the minds of men, and that these beings carried on an intercourse between men and gods, conveying the addresses of men to the gods, and divine benefits to men. Hence demons became the objects of worship. It was supposed also that human spirits, after their departure from the body, became demons, and that the souls of virtuous men, if highly purified, were exalted from demons into gods. In the Scriptures, the Greek δαιμων is rendered devil, and sometimes at least improperly; for nothing is more certain than that different beings are intended by διαβολος and δαιμην. The demons of the New Testament were supposed to be spiritual beings which vexed and tormented men. And in general, the word, in modern use, signifies an evil spirit or genius, which influences the conduct or directs the fortunes of mankind. [See Campbell's Dissert.]