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half sister

American  

noun

  • half sisters
    plural
  1. sister.


half-sister British  

noun

  1. the daughter of either of one's parents by another partner

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Usage

What does half sister mean? A half sister is a sister who is related to her sibling(s) through only one parent. This typically means that they share only one biological parent (not both). For example, when a person’s parent has a daughter with another partner (who is not the person’s parent), the daughter is considered the person’s half sister. The term half brother is used in the same way. Half-sibling is a gender-neutral way of saying the same thing. In contrast, the words stepsister, stepbrother, and stepsibling refer to those who have a sibling relationship (often based on the remarriage of their parents to other partners) but who do not share a biological parent. The word half in half sister and its related terms only refers to the biological relationship. Half sisters may have close relationships with their siblings, and many people simply call their half sister their sister. Modifiers such as maternal and paternal are sometimes used to specify which biological parent the siblings have in common. Example: Over the holidays, I got together with my maternal half sister and my paternal half brother and we had a great time.

Other Word Forms

Noun Inflected Forms

Etymology

Origin of half sister

Middle English word dating back to 1150–1200

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

When she opened her results and saw the mind-boggling truth that her twin was her half sister, Lavinia was distraught - and furious.

From BBC May 2, 2026

Ms. Kuehn met her father’s half sister, Ruth, only once, in 1987.

From The Wall Street Journal Dec. 4, 2025

Breasia was the half sister of Dinkins’ son, and investigators have said both children were staying the night with him at the apartment where he was living with a girlfriend.

From Seattle Times Aug. 10, 2023

Paparazzi spotted Corinne, her half sister Anelise and Anelise’s mom, Kristin Grannis, at the facility in May.

From Los Angeles Times Jul. 10, 2023

Barack also spoke affectionately of another half sister in Nairobi, named Auma.

From "Becoming" by Michelle Obama

He will not be part of Belgium's royal line of succession, unlike his half-sister Princess Louise and half-brothers Prince Aymeric and Prince Nicolas.

From BBC Aug. 20, 2026

The irony is that Sally was also Martha’s half-sister — the product of John Wayles’ relations with an enslaved woman — making her biological kin to the Monticello Association members, too.

From Salon Jul. 27, 2026

Not long afterward, Truelove traveled to New York City, where his half-sister said he spent time in multiple shelters and psychiatric facilities.

From Los Angeles Times Jul. 24, 2026

Barker was also able to dig into his father's background, learning he had three half-brothers and a half-sister.

From BBC Jun. 23, 2026

Within a year, she was delivered of another child, another boy, but as blond as his father and his half-sister, and they named him John, after his father.

From "American Gods" by Neil Gaiman

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