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

The noise of the engines, the mounting anxiety of his wife and sister-in-law, who may have cried out as the plane nose-dived, could only have increased his own. —Jeffrey Eugenides, New Yorker, 4 Apr. 2026

Swift has a lot of close girlfriends to choose from, from Selena Gomez to Gigi Hadid, Brittany Mahomes, future sister-in-law Kylie Kelce, and the Haim sisters. —Rachel Burchfield, InStyle, 2 Apr. 2026

Pegged to his cookbook Kitchen Kickstart, Sam Holland told The Times last August that the Spider-Man star was indeed making his vegetarian recipes for soon-to-be sister-in-law. —Jack Smart, PEOPLE, 2 Apr. 2026

Expected to attend are the groom-to-be’s many siblings, including Ivanka, Tiffany and sister-in-law Lara, who is married to his younger brother Eric. —Madeleine Marr, Miami Herald, 1 Apr. 2026

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