brother-in-law

[bruhth-er-in-law]

noun

plural

brothers-in-law 

1. the brother of one's spouse.

2. the husband of one's sister or brother.

3. the husband of one's spouse's sister or brother.

brother-in-law

noun

1. the brother of one's wife or husband

2. the husband of one's sister

3. the husband of the sister of one's husband or wife

Word History and Origins

Origin of brother-in-law¹

First recorded in 1350–1400; Middle English brother in law(e); brother, in, law ¹; from Middle English in-lawe “in law,” i.e., “a person within the regulation and protection of the law,” based on the prohibition by Roman civil law and, later, Christian canon law, of marriages within four degrees of consanguinity, i.e., up to and including first cousins

Example Sentences

Harrison testified in court Thursday that Rinderknecht claimed he would use the gun in self-defense against his brother-in-law.

Read more on Los Angeles Times

In 1993, I was on vacation in Hazard, Ky. I was visiting my brother-in-law and I told him, “If there’s any Chrysler cars I should look at while I’m in your area, let me know.”

Read more on The Wall Street Journal

The former brother-in-law told investigators that he found another Molotov cocktail near a window before the fire and that Salazar had also driven by his house a few nights before the fire.

Read more on Los Angeles Times

On 28 August, her husband and brother-in-law kidnapped the boy at gunpoint, tortured him and threw his battered body into a river.

Read more on BBC

That was the last time she ever saw her brother-in-law Fahim.

Read more on Salon

Related Words

• aunt 
• cousin 
• father 
• folk 
• mother 
• niece 
• sibling 
• uncle