step-

1. A prefix used before father, mother, brother, sister, son, daughter, child, etc., to indicate that the person thus spoken of is not a blood relative, but is a relative by the marriage of a parent; as, a stepmother to X is the wife of the father of X, married by him after the death of the mother of X. See Stepchild, Stepdaughter, Stepson, etc. Source: opted

2. A prefix used before father, mother, brother, sister, son, daughter, child, etc., to indicate that the person thus spoken of is not a blood relative, but is a relative by the marriage of a parent; as, a stepmother to X is the wife of the father of X, married by him after the death of the mother of X. See Stepchild, Stepdaughter, Stepson, etc. Source: webster

3. A prefix used before father, mother, brother, sister, son,daughter, child, etc., to indicate that the person thus spoken of isnot a blood relative, but is a relative by the marriage of a parent;as, a stepmother to X is the wife of the father of X, married by himafter the death of the mother of X. See Stepchild, Stepdaughter,Stepson, etc. Source: adambom

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