Step-. [AS. steóp-; akin to OFries.
stiap-, stiep-, D. & G. stief-, OHG. stiuf-
, Icel. stj?p-, Sw. styf-, and to AS.
āstēpan, āsteópan, to deprive,
bereave, as children of their parents, OHG. stiufen.] 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,