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

Dear Eric: My sister-in-law made quilts for two of her nieces. —R. Eric Thomas, Chicago Tribune, 23 June 2025

But her sister-in-law has pushed back against these boundaries. —Ashley Vega, People.com, 22 June 2025

Unfortunately, Sam’s missions keep her from fulfilling her maid of honor duties, so Betsy replaces Sam with her soon-to-be sister-in-law (Anna Chlumsky). —Erin Jensen, USA Today, 21 June 2025

The joint statement was issued by several people including Brian Albert, who owned the home where the party took place, and Jennifer McCabe, Albert’s sister-in-law, who was with Read and O’Keefe on the night of O’Keefe’s death. —Patrick Whittle, Twin Cities, 20 June 2025

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