fa-mil'-yar: Is found as an adjective qualifying "friend" and "spirit."
⇒See the definition of familiar in the KJV Dictionary
(1) Used, in a number of Old Testament passages, of spirits which were supposed to come at the call of one who had power over them. 'obh, literally, something "hollow"; compare 'obh, "bottle" (Job 32:19 the King James Version); because the voice of the spirit might have been supposed to come from the one possessed, as from a bottle, or because of the hollow sound which characterized the utterance, as out of the ground (Isa 29:4); or, as some have conjectured, akin to 'ubh, "return" (nekromantis). Probably called "familiar" because it was regarded as a servant (famulus), belonging to the family (familiaris), who might be summoned to do the commands of the one possessing it. The practice of consulting familiar spirits was forbidden by the Mosaic law (Le 19:31; 20:6,27; De 18:11). King Saul put this away early in his reign, but consulted the witch of Endor, who "had a familiar spirit" (1Sa 28:3,7-8,9; 1Ch 10:13). King Manasseh fell into the same sin (2Ki 21:6; 2Ch 33:6); but Josiah put those who dealt with familiar spirits out of the land (2Ki 23:24).
It seems probable, however, that the practice prevailed more or less among the people till the exile (Isa 8:19; 19:3). See "Divination by the 'Ob" in The Expositor T,IX , 157; ASTROLOGY, 1; COMMUNION WITH DEMONS.
(2) "Familiars," "familiar friend," from yadha`, "to know," hence, "acquaintance," one intimately attached (Job 19:14); but more frequently of 'enosh shalom, "man of (my or thy) peace," that is, one to whom the salutation of peace is given (Ps 41:9; Jer 20:10; 38:22; also in Ob 1:7, rendered "the men that were at peace with thee").
Edward Bagby Pollard