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 guest list has not been revealed but the groom’s parents, the Princess Royal and Captain Mark Phillips, are expected to be in attendance, as are his sister and brother-in-law, Mike and Zara Tindall. —Stephanie Bridger-Linning, Vanity Fair, 2 Apr. 2026

She is survived by her sisters, a brother-in-law, a niece and nephews, and by her friend and writing partner Wooten. —Pat Saperstein, Variety, 1 Apr. 2026

Jones is survived by sisters Ellen and Laura, brother-in-law Jim McCarthy, niece Margaret McCarthy and nephews Tommy McCarthy, Todd Hyso and Paul Hyso, along with grand-nieces and cousins. —Erik Pedersen, Deadline, 31 Mar. 2026

No one took better care of my mom than my sister and brother-in-law. —Ethan Beck The Washington Post, Arkansas Online, 27 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