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

My mom was there, my sister, my brother-in-law, my niece who loves musical theater and is actually now studying it in Mexico City. —Sigal Ratner-Arias, Billboard, 11 Mar. 2026

He is survived by his wife of 64 years, Barbara, daughter Michele, son Barry and daughter-in-law Jillian, grandson Sammy, sister Joyce and brother-in-law Jules. —Pat Saperstein, Variety, 6 Mar. 2026

Besides his wife and children, Bertucelli is survived by his parents, Dave and Patty; his sister, Trisha, and his brother-in-law, Michael; nephew Jack; and nieces Ella and Olivia. —Linda Zavoral, Mercury News, 6 Mar. 2026

Earlier this week, Savannah and her siblings, sister Annie and brother-in-law Tommaso Cioni, marked one month since her mother's disappearance by visiting the shrine of yellow flowers, cards, and messages left outside of Nancy's home. —Sharareh Drury, Entertainment Weekly, 5 Mar. 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