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

Jack’s brother-in-law Peter Lawford was one of Monroe’s few true friends. — Laurence Leamer, Vanity Fair, 14 Oct. 2026

Her home was renovated by architectural designer Oliver Freundlich, who is also her brother-in-law; the renovation makes space for her collection. — Hikmat Mohammed, ARTnews.com, 9 Oct. 2026

And for those wondering, Johnny is the brother-in-law of Teresa Marzetti, who is credited with creating this dish at her Ohio restaurant in the 1920s. — Lizzy Briskin, Better Homes & Gardens, 9 Oct. 2026

The court also vacated convictions of terrorism and conspiracy to kill federal officers against Lucas Morton and his brother-in-law, Siraj Wahhaj, the father of the 3-year-old boy who died. — Shelly Bradbury, Denver Post, 8 Oct. 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