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

Watch on Deadline Aimee-Ffion Edwards (Slow Horses) and Aneurin Barnard (Dunkirk) round out the cast as ‘Cis’ and ‘Elfed’, respectively, Richard’s eldest sister and brother-in-law who looked after him after the death of his mother. —Andreas Wiseman, Deadline, 18 Sep. 2024

History Dating Back to 1860 The ties between Girard-Perregaux and Japan date back to 1860, when François Perregaux, brother-in-law of the brand’s founder, established the first Swiss watchmaking office in Yokohama. —Matthew Catellier, Forbes, 17 Sep. 2024

Although his brother-in-law is the future king, William is fully integrated into the Middleton family. —Simon Perry, Peoplemag, 17 Sep. 2024

Ravi was beginning to remind David of his brother-in-law, who had died of a drug overdose a few years earlier. —Max Blau, ProPublica, 8 Sep. 2024

Word History

First Known Use

14th century, in the meaning defined at sense 1

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