From Longman Dictionary of Contemporary Englishstepdaughterstep‧daugh‧ter /ˈstepdɔːtə $ -dɒːtər/ noun [countable] SSFFAMILYa daughter that your husband or wife has from a relationship before your marriage
Examples from the Corpus
stepdaughter• The dining room was indeed where she did find her stepdaughter.• She was filled with compassion for her stepdaughter.• Her stepdaughter was only twelve, still a child, and a child who had had a hard time.• The 53-year-old railway worker abused his stepdaughter and two step-granddaughters in a 12-year reign of terror.• His stepdaughter also left - ostensibly for school.• The stepdaughter, now 21, bore him a child at 16 as a result of being raped.• The stepdaughters ask for various expensive things. 