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Study Dictionary
Sister
SISTER [ISBE]
SISTER - sis'-ter ('achoth): Used repeatedly in the Old Testament of a female (1) having the same parents as another; or (2) having one parent in common, with another, half-sister (Gen 20:12; Lev 18:9), and also (3) of a female belonging to the same family or clan as another, so a kinswoman (Gen 24:60; Job 42:11); (4) also of a woman of the same country (Nu 25:18). (5) Figuratively, the two kingdoms, Israel and Judah, are sisters (Ezek 23:7 ff). (6) Confederate cities are conceived of as sisters (Ezek 16:45 ff). (7) 'Achoth is used of objects which go in pairs, as curtains, each `coupled to its sister' (Ex 26:3,6), and of wings in pairs (Ezek 1:9; 3:13); (8) of virtues or conditions, with which one is closely related: "Say unto wisdom, thou art my sister" (Prov 7:4; compare Job 17:14); (9) of a lover concerning his spouse, as a term of endearment (Song 4:9 f; 5:1 f; 8:8).In the New Testament, adelphe, used (1) in sense of physical or blood kinship (Mt 12:50; 13:56; 19:29; Lk 10:39 f; 14:26; Jn 11:1 ff; 19:25; Acts 23:16); (2) of fellow-members in Christ: "Phoebe, our sister" (Rom 16:1; see also 1 Cor 7:15; 1 Tim 5:1; Jas 2:15); (3) possibly, of a church, "thy elect sister" (2 Jn 1:13).
Edward Bagby Pollard
Also see definition of "Sister" in Word Study