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

Unlike her American sister-in-law, Meghan Markle, the Duchess of Sussex, Catherine tends to prefer to stick to the script. — The New Yorker, New Yorker, 7 Aug. 2026

Among them in traffic was Isabel Torres and her sister-in-law, Karla Diaz, who is pregnant. — Idaho Statesman, 7 Aug. 2026

Dale Schultz Salt Lake City resident Dale Schultz, 66, and his wife were charging their Tesla on Saturday when the shooting occurred, killing him and injuring his longtime spouse, his sister-in-law told ABC Boise affiliate KIVI. — Bill Hutchinson, ABC News, 4 Aug. 2026

Meredith’s sister-in-law, Madeline Gaudreau, was also pregnant at the time of their deaths, and welcomed son Tripp Matthew Gaudreau just four months later. — Rachel McRady, PEOPLE, 4 Aug. 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