'Stepchild' definitions:

Definition of 'stepchild'

From: WordNet
noun
A child of your spouse by a former marriage

Definition of 'Stepchild'

From: GCIDE
  • Stepchild \Step"child`\, n. [AS. ste['o]pcild.]
  • 1. A bereaved child; one who has lost father or mother. [Obs.] [1913 Webster]
  • 2. A son or daughter of one's wife or husband by a former marriage. [1913 Webster]