sister-in-law
Americannoun
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sisters-in-law
plural
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the sister of one's spouse.
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the wife of one's brother or sister.
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the wife of one's spouse's sister or brother.
noun
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the sister of one's husband or wife
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the wife of one's brother
Other Word Forms
Noun Inflected Forms
Etymology
Origin of sister-in-law
First recorded in 1400–50; late Middle English syster in lawe; see origin at sister, in, law 1; from Middle English in-lawe “in law,” i.e., “a person within the regulation and protection of the law,” based on the prohibition by Roman civil law and, later, Christian canon law, of marriages within four degrees of consanguinity, i.e., up to and including first cousins
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
Emmanuel Banuelos spent weeks planning the perfect proposal, selecting a picturesque spot at a Laguna Beach park, enlisting his soon-to-be sister-in-law as a videographer and booking a mariachi band to play his girlfriend’s favorite music.
From Los Angeles Times ● Oct. 5, 2026
In her “wife school” series, Clark interviewed her new sister-in-law, Katie Voetberg, a prairie dress-clad podcast host and mother of six, about how to avoid being a “nagging wife” and a “constant dripping faucet.”
From Salon ● Sep. 28, 2026
Hivsa Walid, her newborn niece and sister-in-law were in the ward next door.
From BBC ● Sep. 16, 2026
My grandmother now wants to revise her will to include my sister, her five great-grandchildren, my sister-in-law, and me.
From MarketWatch ● Aug. 20, 2026
The rest of Ferula’s quarters seemed to Clara to fit precisely with the nightmare that had begun when her sister-in-law appeared in the dining room of the big house on the corner to say goodbye.
From "The House of the Spirits: A Novel" by Isabel Allende
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She exchanged postcards with former sisters-in-law and her first husband’s second wife.
From Salon ● Feb. 9, 2025
"My father, my brother, my sisters-in-law and my friends are gone," says Delfino.
From BBC ● Feb. 7, 2025
Keona’s mother, Rochelle, whispered to her sisters-in-law in Filipino.
From Los Angeles Times ● Aug. 21, 2023
Moreno's wife, one of their daughters, two of his brothers and two sisters-in-law are also among those allegedly connected to the case, Salazar said.
From Reuters ● Feb. 22, 2023
Patti starts pointing out faces and naming my father's cousins and their sisters and sisters-in-law and brothers and brothers-in-law.
From "Born Behind Bars" by Padma Venkatraman
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