sis·​ter | \ ˈsi-stər How to pronounce sister (audio) \

Definition of sister

1 : a female who has one or both parents in common with another
2 often capitalized
a : a member of a women's religious order (as of nuns or deaconesses) especially : one of a Roman Catholic congregation under simple vows
b : a girl or woman who is a member of a Christian church
3a : a girl or woman regarded as a comrade
b : a girl or woman who shares with another a common national or racial origin especially : a Black girl or woman
4 : one that is closely similar to or associated with another sister cities
5 chiefly British : nurse
6a : girl, woman
b : person usually used in the phrase weak sister
7 : a member of a sorority

Examples of sister in a Sentence

The sisters live in the convent.
Recent Examples on the Web Ann Redding and Matt Danzer wanted Thai Diner to be the more casual sister to Uncle Boons, one of the city’s defining restaurants of the past decade. New York Times, "17 Restaurants Where New Yorkers Can Make Up for Lost Time," 20 Apr. 2021 Arlana Saddler, the youngest sister of missing worker Gregory Walcott, told The Associated Press that families were told during a Sunday night meeting with officials that a body had been found but not yet identified., "Search for missing crew off Louisiana to be suspended, Coast Guard says," 19 Apr. 2021 David Armstrong-Jones, Earl of Snowdon: Son of Princess Margaret, who was the queen’s sister. Washington Post, "Who are the 30 people attending Prince Philip’s funeral?," 16 Apr. 2021 After mom died, the sister claimed the account was 100% hers alone as the surviving joint owner. Christine Fletcher, Forbes, "5 Ways To Protect Your Bank Account After Your Die," 16 Apr. 2021 The sister of a BBC producer may have joined the Irish Republican Army. New York Times, Star Tribune, "New York Times bestsellers," 27 Apr. 2021 Simmerly was the daughter of late Genevieve (nee Coughlin) and Nicholas Simmerly; sister of the late Carol Madison, Robert Simmerly and Timothy Simmerly and extended family members and friends. Carol Kovach, cleveland, "Taste of Lakewood returns as Taste of Lakewood Restaurant Week: A Place in the Sun," 27 Apr. 2021 Jyah LoVett, the sister of former Burbank Providence standout Marcus LoVett Jr., made quite a debut for Pasadena Muir. Eric Sondheimer Columnist, Los Angeles Times, "Prep Rally: Sierra Canyon picks up where it left off in boys’ basketball," 26 Apr. 2021 To announce the news to their kids, Gadot and Varsano set up a little cupcake party, with each family member getting their own cupcake, plus an extra for the unborn sister. Elizabeth Logan, Glamour, "Gal Gadot Got Tipsy and Chopped Off the Tip of Her Finger," 23 Apr. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'sister.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of sister

before the 12th century, in the meaning defined at sense 1

History and Etymology for sister

Middle English suster, sister, partly from Old English sweostor and partly from Old Norse systir sister; akin to Latin soror sister, Sanskrit svasṛ

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Time Traveler for sister

Time Traveler

The first known use of sister was before the 12th century

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Statistics for sister

Last Updated

30 Apr 2021

Cite this Entry

“Sister.” Dictionary, Merriam-Webster, Accessed 8 May. 2021.

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More Definitions for sister



English Language Learners Definition of sister

: a girl or woman who has one or both of the same parents as you
informal used when talking to a woman
: a member of a religious community of women


sis·​ter | \ ˈsi-stər How to pronounce sister (audio) \

Kids Definition of sister

1 : a female person or animal related to another person or animal by having one or both parents in common
2 : a member of a religious society of women : nun
3 : a woman related to another by a common tie or interest

Other Words from sister

sisterly adjective


sis·​ter | \ ˈsis-tər How to pronounce sister (audio) \

Medical Definition of sister

chiefly British
: a head nurse in a hospital ward or clinic broadly : nurse

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