Other forms: half-sisters
A half-sister is a sister who shares only one of your parents. My half-sister.
The word says nothing about how close anybody is, which is why many people drop the half. A half-sister is a full sister in law for most purposes, including inheritance.
1nounhalf-sisterA sister who shares only one of your parents.
“His half-sister was eleven years younger and lived abroad.”
half-sister is a relative.
Half plus sister, describing the shared half of the parentage.
Middle English
half
English
half
English, today
half-sister
Equivalent to half + sister. half comes from Middle English half. From Middle English half, halfe from Old English healf (“half”); as a noun, 'half', 'side', 'part', from Proto-West Germanic halb, from Proto-Germanic halbaz. 2
Etymology from Wiktionary, CC BY-SA