Definition(s):

“1. A family that is formed when separate families are united by marriage or other circumstance; a stepfamily. 2. Various kinship or nonkinship groups whose members reside together and assume traditional family roles” (Barker, 2003, p. 46).
“…has a role structure in which at least one parent has been previously married and which includes children from one or both of these marriages” (Johnson, 2000, p. 119).

Barker, R.L. (2003). The social work dictionary (5th ed.). Washington, DC: NASW Press. Johnson, A.G. (2000). The Blackwell dictionary of sociology (2nd ed.). Malden, MA: Blackwell Publishers, Inc.