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

Fortuitously, the team’s powers that be had set up shop at Lurie’s lakefront mansion in Palm Beach, about 45 miles up the Florida coast from Sirianni, who was holed up at the house of his brother-in-law and sister-in-law. —Michael Silver, New York Times, 16 June 2026

The company, which at one point operated some 200 cafes and expanded into other food service endeavors, was founded by Joseph Lyons (after whom the company was named) and his brothers-in-law, Isidore and Montague Gluckstein. —Leigh Anne Miller, ARTnews.com, 15 June 2026

My brothers-in-law and their spouses give their parents only limited amounts of time on holidays and limited physical assistance to their parents only if my husband begs for help. —Jeanne Phillips, Mercury News, 13 June 2026

Jim played Kevin Doneghy, the brother-in-law of a young woman left in a permanent coma after a medical error in a Catholic hospital. —Carl Kurlander, Deadline, 13 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