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

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Examples of sister in a Sentence

The sisters live in the convent.
Recent Examples on the Web In 1990, Melissa’s brother Kevin was 12 and their sister Jenn was 14. Grace Stetson, NBC News, "Family wants justice in 1990 cold case murder of Suffolk County Detective Dennis Wustenhoff killed by car bomb in front of Long Island home," 21 Feb. 2020 Gutierrez had a deep well of courage even as a little boy, his sister, Jordan Gutierrez, remembered. Sig Christenson,, "Family, friends salute slain GI in his San Antonio hometown," 21 Feb. 2020 Gannon's younger sister, Laila, also sat down with the parents for the statement. Clayton Sandell, ABC News, "The disappearance of Gannon Stauch: A timeline of the case," 18 Feb. 2020 Counterfeit checks had been deposited in bank accounts belonging to Massa’s mother, and at least one money order had been made out to Massa’s sister, Leire, using her real name and address. Justin Rohrlich, Quartz, "How not to steal $1.5 million: Inside an Instagram influencer’s alleged debit card scam," 15 Feb. 2020 His older sister, who's now officially of voting age, scoffs at this optimism, convinced the election is corrupt and that voting makes no difference anyway. Robyn Bahr, The Hollywood Reporter, "'The Conners: Live from Lanford': TV Review," 12 Feb. 2020 Karrie told the officer that her younger sister was safe: LT. Erin Moriarty, CBS News, ""I had to choose": Did a father brainwash his daughter to help plan her mother's murder?," 8 Feb. 2020 Audrey assumed Bode would arrive late just like his 2-year-old sister, Ember — she was born 12 days past her due date. Selena Barrientos, Good Housekeeping, "Audrey Roloff Posts Emotional Instagram About Baby Bode's Birth," 8 Feb. 2020 In the meantime, Wulfmeier said her sister is relying on her faith to get her through this. Kristen Jordan Shamus, Detroit Free Press, "Coronavirus outbreak: Sterling Heights woman is on quarantined cruise ship in Japan," 7 Feb. 2020

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

25 Feb 2020

Cite this Entry

“Sister.” Dictionary, Merriam-Webster, Accessed 28 Feb. 2020.

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More Definitions for sister


How to pronounce sister (audio)

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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More from Merriam-Webster on sister

Thesaurus: All synonyms and antonyms for 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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