half-sister
US /ˈhæfˌsɪs.tər/
UK /ˈhæfˌsɪs.tər/
1.
a sister with whom one shares only one parent
:
•
My half-sister and I have the same mother but different fathers.
•
She grew up with her half-sister after their parents remarried.
a sister with whom one shares only one parent