mother-in-law

noun

moth·​er-in-law ˈmə-t͟hər-ən-ˌlȯ 

ˈmət͟h-rən-, 

ˈmə-t͟hərn-

plural mothers-in-law ˈmə-t͟hər-zən-ˌlȯ 

1

: the mother of one's spouse

2

archaic : stepmother

Examples of mother-in-law in a Sentence

Recent Examples on the Web

Around the same time, my mother-in-law required more care, resulting in an unplanned move to a nearby assisted living facility. — Kelly Phillips Erb, Forbes.com, 23 July 2026

Malcolm-Jamal Warner’s widow, Tenisha Warner, seemingly hinted at the distance between her and her mother-in-law, Pamela Warner, in a CBS Mornings interview with Gayle King. — Mekishana Pierre, Entertainment Weekly, 22 July 2026

At the annual Monaco Red Cross Ball, Princess Charlene of Monaco served up old Hollywood glamour—not unlike her late mother-in-law, Princess Grace, who before marrying into the Monegasque royal family was movie star Grace Kelly. — Rachel Burchfield, InStyle, 22 July 2026

Tenisha Warner, the actor’s wife and mother to his daughter, on Monday filed a civil complaint against her mother-in-law alleging breach of contract. — Alexandra Del Rosario, Los Angeles Times, 22 July 2026

Word History

First Known Use

14th century, in the meaning defined at sense 1

Rhymes for mother-in-law

• avoirdupois
• aa
• aha
• bashaw
• bradshaw
• byelaw
• bylaw
• chainsaw
• cheraw
• coleslaw
• crenshaw
• dada

Kids Definition

mother-in-law

noun

moth·​er-in-law

ˈmət͟h-(ə-)rən-ˌlȯ, 

ˈmət͟h-ərn-ˌlȯ

plural mothers-in-law

ˈmət͟h-ər-zən-

: the mother of one's husband or wife