Dictionary.com
Thesaurus.com
Synonyms

brother-in-law

American  
[bruhth-er-in-law] / ˈbrʌð ər ɪnˌlɔ /

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 British  

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of brother-in-law

First recorded in 1350–1400; Middle English brother in law(e); see origin at 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

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Anwar Usman, the court’s then-chief justice, is Widodo’s brother in law.

From Seattle Times • Mar. 20, 2024

Ibn Wahhaj, his brother in law, Lucas Morton, and sisters Hujrah Wahhaj and Subhannah Wahhaj are in Taos County jail awaiting trial.

From Reuters • Aug. 24, 2018

“My brother in law is a Cowdenbeath fan and tells a great story about the time Eddie the Eagle visited Central Park as part of a radio series on ‘Great Sporting Losers’,” says Simon McMahon.

From The Guardian • May 6, 2017

I had a brother in law who owns a restaurant and he said they made food salty to get customers to buy more drinks.

From New York Times • Apr. 25, 2017

He had no reason, public or private, for preferring his sister in law to his brother in law, if his brother in law were bred a Protestant.

From The History of England, from the Accession of James II — Volume 4 by Macaulay, Thomas Babington Macaulay, Baron

Vocabulary.com logo
by dictionary.com

Look it up. Learn it forever.

Remember "brother-in-law" for good with VocabTrainer. Expand your vocabulary effortlessly with personalized learning tools that adapt to your goals.

Take me to Vocabulary.com