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

Depending on the size of the party, my mother-in-law prepares the table hours, or even a day or so, in advance. — Elly Leavitt, Vogue, 22 Sep. 2026

When his mother-in-law arrived at the home soon after, Flynn wailed and collapsed on the front porch, bodycam footage showed. — Nicki Brown, CNN Money, 19 Sep. 2026

Her late mother-in-law, Jackie, was also 34 when her husband was assassinated during a motorcade in Dallas in November 1963—months after Stas gifted her the watch. — Bailey Bujnosek, InStyle, 17 Sep. 2026

Our essential oil diffuser, nebulizer, and basket full of oils have been happily taken in by my mother-in-law, and are now scenting her living and guest room. — The Spruce, 14 Sep. 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