sis·ter | \ˈsi-stər \

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

Celestine, the sister of Jeremiah and Ciera's father, petitioned to adopt the children in May 2007. Joe Heim And Julie Tate,, "As children begged for help, adoption system failed them," 13 July 2018 The sisters work with Vatsalya, a non-governmental agency that oversees their day-to-day program in India. Kirby Adams, The Courier-Journal, "These one-of-a-kind textiles are empowering Louisville women," 13 July 2018 Chuck is the brother of Abud’s grandfather, while his wife Lila is the sister of Joseph’s mother. Lori Higgins, Detroit Free Press, "What soccer-loving uncle taught 2 top Michigan teachers," 13 July 2018 The sisters later moved to the South American nation of Guyana, to the clearing in the jungle that Jones called Jonestown. Will Higgins, Indianapolis Star, "She woke up in Jonestown — everyone was dead," 13 July 2018 The search for self-expression expanded at the University of Southern California, where the itinerant sisters—raised by Palestinian parents between Riyadh, London, and Dubai—graduated with double majors in film production and fine art. Kate Branch, Vogue, "This DJ Sister Act Is the Only Beauty Inspiration You Need This Summer," 12 July 2018 Starting out with the clarifying shampoo helps remove any product buildup, the Stirrup sisters add, while the moisturizing one helps hydrate and detangle hair. Devon Abelman, Allure, "11 Curl-Washing Tips From Real Women With Kinky-Curly Hair," 12 July 2018 Nettie, the sister who becomes an African missionary (endearing N’Jameh Camara), reveals the vastness of the world beyond rural Georgia. Lawrence Toppman, charlotteobserver, "A deeper ‘Purple’ than we’ve seen reaches Charlotte via Broadway Lights," 12 July 2018 First, Khloé Kardashian, who was the last sister to continue working with Monica Rose, parted ways with the stylist. Colleen Kratofil,, "Sofia Richie Is Now Working with Former Kardashian Stylist Monica Rose," 12 July 2018

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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Phrases Related to sister

little brother/sister

sister city

Statistics for sister

Last Updated

7 Oct 2018

Look-up Popularity

Time Traveler for sister

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

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English Language Learners Definition of sister

: a girl or woman who has one or both of the same parents as you

—used when talking to a woman

: a member of a religious community of women


sis·ter | \ˈsi-stər \

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 \

Medical Definition of sister 

chiefly British

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

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Comments on sister

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lying above or upon

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