[ muhth-er-in-law ]
/ ˈmʌð ər ɪnˌlɔ /

noun, plural moth·ers-in-law.

the mother of one's husband or wife.


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Origin of mother-in-law

1350–1400; Middle English modyr in lawe Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Example sentences from the Web for mother-in-law

British Dictionary definitions for mother-in-law


noun plural mothers-in-law

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