Stepsisnoun
A stepsister.
Stepsisternoun
The daughter of one's stepparent who is not the daughter of either of one's parents.
Stepsisternoun
The stepdaughter of one's parent which is not one's half-sister.
Stepsisternoun
A daughter of one's stepfather or stepmother by a former marriage.
Stepsisternoun
a sister who has only one parent in common with you