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Synonyms

mother-in-law

American  
[muhth-er-in-law] / ˈmʌð ər ɪnˌlɔ /

noun

plural

mothers-in-law
  1. the mother of one's spouse.


mother-in-law British  

noun

  1. the mother of one's wife or husband

"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 mother-in-law

First recorded in 1350–1400; Middle English moder in lawe; see origin at mother 1 ( def. ), in ( def. ), law 1 ( def. ); 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.

“Wife and mother in law trapped” read one.

From Washington Post • Apr. 20, 2023

The entire Baquet family - Eddie, Myrtle, his wife, his mother in law, his five boys including Wayne - would live in the back of the bar.

From Washington Times • Mar. 21, 2021

"My mother in law Kris Jenner ... makes the best music playlist," West, 43, tweeted on Tuesday.

From Fox News • Jan. 6, 2021

Somehow my mother in law was able to snag one for me last week as a birthday present.

From Slate • May 5, 2020

P. S. My mother in law says, if you come this way, call.

From The Lock and Key Library The most interesting stories of all nations: Real life by Hawthorne, Julian

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