brother-in-law

noun

broth·​er-in-law ˈbrə-t͟hər-ən-ˌlȯ How to pronounce brother-in-law (audio)
ˈbrət͟h-rən-, 
ˈbrə-t͟hərn-
plural brothers-in-law ˈbrə-t͟hərz-ən- How to pronounce brother-in-law (audio)
1
: the brother of one's spouse
2
a
: the husband of one's sibling
b
: the husband of one's spouse's sibling

Examples of brother-in-law in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Lindsey’s sister and brother-in-law had their own RV park upriver. — Abe Streep, ProPublica, 21 Oct. 2026 Matt, then the goalkeeper for the New England Revolution, their three young boys, a brother-in-law and Nicole’s parents, John and Karen. — Eric Sondheimer, Los Angeles Times, 21 Oct. 2026 Following the death of his sister Kelly Bryan and brother-in-law Ben Lee Cheshire, the couple took in Kelly and Ben’s three children to raise alongside their sons. — Tracy Wright, FOXNews.com, 19 Oct. 2026 He is survived by his sister, Judy; brother-in-law, Stefan and nieces, Jenna and Lily. — Isabelle Farina, Variety, 19 Oct. 2026 See All Example Sentences for brother-in-law

Word History

First Known Use

14th century, in the meaning defined at sense 1

Time Traveler
The first known use of brother-in-law was in the 14th century

Rhymes for brother-in-law

See All Rhymes for brother-in-law

Browse Nearby Words

brother-in-arms
brother-in-law
Brother Jonathan
See all Nearby Words

Cite this Entry

“Brother-in-law.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/brother-in-law. Accessed 22 Oct. 2026.

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Kids Definition

brother-in-law

noun
broth·​er-in-law
ˈbrət͟h-(ə-)rən-ˌlȯ, 
ˈbrət͟h-ərn-ˌlȯ
plural brothers-in-law
ˈbrət͟h-ər-zən-
1
: the brother of one's spouse
2
: the husband of one's sibling or of one's spouse's sibling
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