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

Over the weekend, members of the MLBPA’s eight-player executive subcommittee were presented with exchanges between Clark and his sister-in-law. —Andy McCullough, New York Times, 18 Feb. 2026

Major League Baseball Player’s Association executive director Tony Clark resigned Tuesday after an investigation revealed an inappropriate relationship with his sister-in-law, a union employee, ahead of what’s expected to be a tenuous labor negotiation. —Shawn McFarland, Dallas Morning News, 18 Feb. 2026

The employee was his sister-in-law, the person confirmed. —Bill Shaikin, Los Angeles Times, 18 Feb. 2026

Clark was allegedly engaging in an inappropriate relationship with his sister-in-law, who had been hired by the MLBPA in 2023. —Abbey Mastracco, New York Daily News, 17 Feb. 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