sister-in-law

noun

sis·​ter-in-law ˈsi-st(ə-)rən-ˌlȯ 

-tərn-ˌlȯ

plural sisters-in-law ˈsi-stər-zən-ˌlȯ 

1

: the sister of one's spouse

2

a

: the wife of one's sibling

b

: the wife of one's spouse's sibling

Examples of sister-in-law in a Sentence

Recent Examples on the Web

Still, the woman didn’t budge and has since been uninvited to her sister-in-law’s wedding. —Meredith Wilshere, People.com, 6 July 2025

Ralph Lauren, a designer also worn by Middleton’s sister-in-law, Meghan Markle, has several pieces featured in Kate Middleton’s royal wardrobe. —Julia Teti, Footwear News, 2 July 2025

Fossett’s sister-in-law Frances Hern was sent over as well in 1806. —Jeff Suess, The Enquirer, 2 July 2025

And the other was her sister-in-law, who was well brought up and very shy and had a terrible drinking problem and was abused by her husband and was just holding on to life so hard. —Jennifer Cunningham h. Alan Scott, MSNBC Newsweek, 2 July 2025

Word History

First Known Use

15th century, in the meaning defined at sense 1

Rhymes for sister-in-law

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

Kids Definition

sister-in-law

noun

sis·​ter-in-law

ˈsis-t(ə-)rən-ˌlȯ,

-tərn-ˌlȯ

plural sisters-in-law

-tər-zən-

1

: the sister of one's spouse

2

a

: the wife of one's sibling

b

: the wife of one's spouse's sibling