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 brothers-in-law (audio) \

Definition of brother-in-law

1 : the brother of one's spouse
2a : the husband of one's sibling
b : the husband of one's spouse's sibling

First Known Use of brother-in-law

14th century, in the meaning defined at sense 1

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Time Traveler for brother-in-law

Time Traveler

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

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Cite this Entry

“Brother-in-law.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/brother-in-law. Accessed 24 Feb. 2020.

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More Definitions for brother-in-law

brother-in-law

noun
How to pronounce brother-in-law (audio)

English Language Learners Definition of brother-in-law

: the brother of your husband or wife
: the husband of your sister

brother-in-law

noun
broth·​er-in-law | \ ˈbrə-t͟hər-ən-ˌlȯ \
plural brothers-in-law

Kids Definition of brother-in-law

1 : the brother of a person's husband or wife
2 : the husband of a person's sister

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More from Merriam-Webster on brother-in-law

Rhyming Dictionary: Words that rhyme with brother-in-law

Spanish Central: Translation of brother-in-law

Nglish: Translation of brother-in-law for Spanish Speakers

Britannica English: Translation of brother-in-law for Arabic Speakers

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