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

When his wife’s parents are found dead in a burning house, and his wife, Diya, and her sister-in-law nearly dead from stab wounds, Tavish Advani becomes the primary suspect. —Sandra Dallas, Denver Post, 19 Apr. 2026

Dennis was going to take a car trip with his brother, sister-in-law, niece and his brother’s dog. —Abigail Van Buren, Boston Herald, 19 Apr. 2026

Ashley searched the property, then called her sister-in-law, Heather, to ask if Athena was at her home up the hill. —Samantha Stutsman, PEOPLE, 18 Apr. 2026

Realizing the attacker was her sister-in-law, Antonia Eastwood, who is married to Gemma’s older brother, Ashley, Gemma grabbed her by the hair, but Eastwood managed to get away. —Louis Casiano, FOXNews.com, 17 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