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 The movie features Hall’s character, Megan, and her journey to make it to her sister’s wedding. al, 14 May 2022 While discussing the more chaotic consequences of working from home—Eva Mendes is the co-owner of the cleaning brand Skura Style—the actor even shared a sweet anecdote about her girls, revealing that Amada refers to her older sister as Essie. Emily Tannenbaum, Glamour, 13 May 2022 The living room looks out toward the deck and pool, and the backyard that features a stone path leading to a gate connecting Eberle’s property to her sister Julie Kelley’s, who lives right next door. Lennie Omalza, The Courier-Journal, 12 May 2022 Officers learned a dispute occurred when the girl ate some McDonald’s fries that belonged to her sister and the mother disciplined her for her actions. cleveland, 12 May 2022 In addition to her sister, she is survived by her father; a brother, Jacob Nussbaum; and a daughter, Taina Rodriguez. New York Times, 12 May 2022 The other timeline sees Charlie's Angels star Ella Balinska as an older version of Jade fighting for survival in 2036 London and having flashbacks to what happen to her sister leading up to the start of the global zombie apocalypse. Nick Romano,, 12 May 2022 In a video featuring the whole family, Alec, Hilaria and their six children are each seen throughout the clip giving advice to their baby sister on the way. Georgia Slater,, 9 May 2022 But there was mud on the tires, a sign to Grinstead’s sister that something was wrong. Alexis Stevens, ajc, 6 May 2022 See More

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.

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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Dictionary Entries Near sister



sister block

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Statistics for sister

Last Updated

24 May 2022

Cite this Entry

“Sister.” Dictionary, Merriam-Webster, Accessed 29 May. 2022.

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More Definitions for sister


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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