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) \

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

Keep scrolling for more

Learn More About brother-in-law

Time Traveler for brother-in-law

Time Traveler

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

See more words from the same century

Dictionary Entries Near brother-in-law

brother-in-arms

brother-in-law

Brother Jonathan

See More Nearby Entries 

Statistics for brother-in-law

Cite this Entry

“Brother-in-law.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/brother-in-law. Accessed 27 May. 2022.

Style: MLA
MLACheck Mark Icon ChicagoCheck Mark Icon APACheck Mark Icon Merriam-WebsterCheck Mark Icon

More Definitions for brother-in-law

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 spouse
2 : the husband of a person's sibling
3 the husband of a person's spouse's sibling

More from Merriam-Webster on brother-in-law

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

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

WORD OF THE DAY

Test Your Vocabulary

Eponyms: Words Named After People

Spell It

Can you spell these 10 commonly misspelled words?

TAKE THE QUIZ
Universal Daily Crossword

A daily challenge for crossword fanatics.

TAKE THE QUIZ
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!