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

Fighting back tears, Brito said his brother and sister-in-law died while protecting their 12-year-old son, Samuel. — Ivan Taylor, CBS News, 30 June 2026

In a picture shared to Instagram by Alexis on Thursday, Mary-Kate and Ashley stood next to their new sister-in-law and dad, Dave Olsen, in their signature long black gowns. — Leigh Blickley, Entertainment Weekly, 29 June 2026

At the same time, Simosa Verde’s sister-in-law and three children remain missing beneath the rubble of a collapsed building. — Antonio María Delgado, Miami Herald, 29 June 2026

Taylor’s parents, Andrea and Scott Swift, and brother Austin Swift, along with Travis’s parents, Donna and Ed Kelce, his brother Jason Kelce, and his sister-in-law Kylie Kelce are all expected to be attending. — Bailey Bujnosek, InStyle, 27 June 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