brother-in-law

noun

broth·​er-in-law ˈbrə-t͟hər-ən-ˌlȯ 

ˈbrət͟h-rən-, 

ˈbrə-t͟hərn-

plural brothers-in-law ˈbrə-t͟hərz-ən- 

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

The three-time Super Bowl champ, 36, enjoyed quality time with his male friends in Southern California, including big brother and former Philadelphia Eagles center Jason Kelce as well as future brother-in-law Austin Swift, according to multiple outlets. — Jami Ganz, New York Daily News, 22 June 2026

My brother-in-law and nephew traveled all the way from Tokyo to my home state to see the game with my son and me. — Bryan Preston, FOXNews.com, 20 June 2026

There are no arrest warrants against her, unlike her husband and brother-in-law, who are on the run. — CBS News, 19 June 2026

Her grandmother Ruth Roche, Baroness Fermoy, was a lady-in-waiting to Queen Elizabeth, the Queen Mother, and her brother-in-law Lord Robert Fellowes worked in the royal household, eventually rising to the role of Queen Elizabeth's private secretary. — Janine Henni, PEOPLE, 19 June 2026

Word History

First Known Use

14th century, in the meaning defined at sense 1

Rhymes for brother-in-law

• avoirdupois
• aa
• aha
• bashaw
• bradshaw
• byelaw
• bylaw
• chainsaw
• cheraw
• coleslaw
• crenshaw
• dada

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