sister

noun

sis·​ter ˈsi-stər 

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

3

a

: 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

6

a

: 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

That much is clear from Ted’s casual visit to the oddities shop run by Dani’s blind twin sister, Darcy (also Bracken in a dual role). —Carlos Aguilar, Variety, 16 Apr. 2024

His younger sister, Rosemary Kennedy, had been born with intellectual disabilities — and her treatment is illustrative of some of the horrors of the asylum era. —Greg Rosalsky, NPR, 16 Apr. 2024

Okiku’s sister, Hazel Castellano, last month filed a wrongful death lawsuit against the landlord in Sacramento Superior Court. —Theresa Clift, Sacramento Bee, 16 Apr. 2024

Indy is survived by two older brothers and one older sister: Ocean, Kingston, and Rio, respectively. —Sara Vallone, Miami Herald, 16 Apr. 2024

Liev Schreiber's son is hoping for some more time with his baby sister. —Hannah Sacks, Peoplemag, 15 Apr. 2024

His sister Ren, played by Christy Carlson Romano, was always trying to kill the fun. —Ew Staff, EW.com, 15 Apr. 2024

Chilling video from Chile captured a nun walking down the street with a wheeled suitcase that police later discovered to contain her fellow sister’s corpse. —Peter Aitken, Fox News, 13 Apr. 2024

The museum documents the lynching of a 3-year-old girl, along with her 10-year-old sister — just two of dozens of children killed, often while law enforcement watched. —Anita Chabria, Los Angeles Times, 4 Apr. 2024

Word History

Etymology

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

First Known Use

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

Phrases Containing sister

• big sister
• brother/sister/comrade in arms
• foster brother/sister
• half sister
• little brother/sister
• sister chromatid
• sister city
• sister-in-law
• sob sister
• soul sister
• weak sister

Kids Definition

sister

noun

sis·​ter ˈsis-tər 

1

: a female who has one or both parents in common with another individual

2

often capitalized : a member of a religious community of women : nun

3

a

: a fellow female member of a group

b

: a girl or woman who shares a common national or racial origin with another

4

: one that is closely similar to or associated with another

sister schools

sister ships

5

chiefly British : nurse entry 1 sense 2

sisterly adjective or adverb

Medical Definition

sister

noun

sis·​ter ˈsis-tər 

chiefly British

: a head nurse in a hospital ward or clinic

broadly : nurse