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

There’s also space to add a mother-in-law or nanny’s apartment. —Sara B. Hansen, Denver Post, 4 Apr. 2026

Kylie said that the same sentiment holds for her mother-in-law Donna Kelce, revealing that The Traitors alum recently faced an uncomfortable line of questioning by TMZ. —Lara Walsh, InStyle, 2 Apr. 2026

One Sunday supper, over red wine and meatballs, my Italian mother-in-law announced that her nephew—our cousin, one of the youngest in a field of 13—was getting married. —Lara Kramer, Condé Nast Traveler, 1 Apr. 2026

On Christmas Eve, Florida’s new coach — along with his wife, four children, mother-in-law and her dog — broke bread with the Baughs in their Atlanta home, laying the groundwork for his return. —Edgar Thompson, The Orlando Sentinel, 1 Apr. 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