What word or phrase does your mother always say?
masc. proper name, Biblical third son of Adam, literally "set, appointed," from Hebrew Sheth, from shith "to put, set." The Gnostic sect of Sethites (2c.) believed Christ was a reappearance of Seth, whom they venerated as the first spiritual man.
appointed; a substitute, the third son of Adam and Eve (Gen. 4:25; 5:3). His mother gave him this name, "for God," said she, "hath appointed me [i.e., compensated me with] another seed instead of Abel, whom Cain slew."