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

Emma Roberts snapped selfies in a scarlet suit, while the Haim sisters created their own photoshoot-worthy moments in autumnal hues of copper, oxblood, and cream. Vogue, "Chloé and MOCA Make a Splash With Two New Exhibitions," 28 Nov. 2018 Eventually his store became synonymous with a kind of ostentatious Hollywood glamour—the L.A. of Alfred Bloomingdale and the Gabor sisters and the pool at the Beverly Hills Hotel. Maer Roshan, Town & Country, "In Beverly Hills and Beyond, Bijan Carries on a Tradition of Excess and Exclusivity," 22 Oct. 2018 Stella Valle: This online jewelry store was started by sisters Ashley Jung and Paige Dellavalle, both West Point graduates and Army veterans. Jacqueline Detwiler, Popular Mechanics, "Thank You For Your Service. Now What?," 17 Oct. 2018 Just in time for Halloween, Smith reimagined the famous waterfront home of the Owens sisters. Alyssa Fiorentino, House Beautiful, "This Girl Recreated The 'Practical Magic' House On The Sims And It's Insane," 11 Oct. 2018 Before the fire trucks arrived, Vanasse’s sister was able to drive off with her bulldog, but Vanasse turned back to rescue an absent neighbor’s elderly poodle. Sara Jean Green, The Seattle Times, "Cause of massive North Queen Anne lumber yard fire remains under investigation," 13 Nov. 2018 The Girl in the Spider’s Web is a murky, conventional thriller The plot of The Girl in the Spider’s Web has to do with Lisbeth’s sister Camilla (Sylvia Hoeks), who went essentially unmentioned in Larsson’s original trilogy. Alissa Wilkinson, Vox, "Lisbeth Salander returns in the limp, faux-feminist The Girl in the Spider’s Web," 9 Nov. 2018 Land Ark’s newest home on wheels shares plenty of DNA with its sister RV, the Drake. Liz Stinson, Curbed, "Ultra-stylish tiny house comes with fold-down deck," 9 Nov. 2018 Played by Sylvia Hoeks and always dressed in ruby red, Lisbeth’s sister Camilla was out for blood. Lauren Sanchez, Vogue, "The Girl in the Spider’s Web," 5 Nov. 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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Statistics for sister

Last Updated

2 Dec 2018

Look-up Popularity

Time Traveler for sister

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

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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

—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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More from Merriam-Webster on sister

Rhyming Dictionary: Words that rhyme with sister

Spanish Central: Translation of sister

Nglish: Translation of sister for Spanish Speakers

Britannica English: Translation of sister for Arabic Speakers

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