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

That’s my sister, not my sister-in-law. —Alyssa Modos, PEOPLE, 4 May 2026

Atkinson said ‌the car had once belonged to Starmer, ⁠one house was managed by a company of which the prime minister ⁠had once been director and shareholder, and the other home was still owned by him and his sister-in-law was ‌living there. —Reuters, NBC news, 29 Apr. 2026

She is survived by her sister Sue, brother-in-laws Jack and Steve, sister-in-law Shannon and seven nephews and nieces. —Dan Albano, Oc Register, 25 Apr. 2026

Community remembers teen killed Michelle Gonzalez, 17, was one of the victims, according to her sister-in-law. —Alexa Herrera, CBS News, 24 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