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

Robinson said her brother-in-law Gary had just walked out of the bathroom just moments before the tree fell. —Paul Burton, CBS News, 17 Mar. 2026

The seventh episode finally reveals the dark secret that has bonded Kay with her detective brother-in-law Pete Marino (played by Bobby Cannavale in the present day, and Cannavale’s real-life son Jacob Lumet in the past). —Max Gao, HollywoodReporter, 16 Mar. 2026

And one of the people who got accused very quickly was Savannah’s brother-in-law, Tommaso Cioni. —Lizzie Lanuza, StyleCaster, 16 Mar. 2026

And when her brother-in-law, Stanley (Marlon Brando), rapes her, her descent into madness was made all the more vivid and believable by Leigh's precise depiction of vulnerability and instability. —Darren Franich, Entertainment Weekly, 15 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