From Longman Dictionary of Contemporary Englishhalf-sisterˈhalf-ˌsister ●●○ noun [countable] SSFa sister who is the daughter of only one of your parents → half-brother
Examples from the Corpus
half-sister• Tut, meanwhile, married his half-sister, Ankhesenamen.• The more substantial is that the justices directed that T.'s contact with her older half-sister should be supervised.• Mrs Aitken, meet Shiona Fergusson, Kirsty's half-sister.• Mitchell rented it from the half-sister of the owner, a schoolteacher gone to Toronto with her three chil-dren.• The bees, they found, were more aggressive towards half-sisters.• Apart from his brother, he had one sister, one half-brother, and two half-sisters.• Mrs Grant invites her younger half-sister Mary Crawford to live with her at the parsonage. 