Merriam-Webster Logo
SINCE 1828
Menu
×

An Encyclopædia Britannica Company

sister-in-law

noun sis·ter-in-law \ ˈsi-st(ə-)rən-ˌlȯ , -tərn-ˌlȯ \
See What's Trending Now See More Trending Words
plural sisters-in-law play \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

See sister-in-law defined for English-language learners

See sister-in-law defined for kids

First Known Use of sister-in-law

15th century

in the meaning defined at sense 1

See Words from the same year
NEW! Time Traveler

SISTER-IN-LAW Defined for English Language Learners

sister-in-law

noun

  • : the sister of your husband or wife

  • : the wife of your brother

SISTER-IN-LAW Defined for Kids

sister-in-law

noun sis·ter-in-law \ ˈsi-stər-ən-ˌlȯ \
plural sisters-in-law
1 : the sister of someone's husband or wife
2 : the wife of someone's brother

Learn More about sister-in-law

  1. See words that rhyme with sister-in-law Spanish Central: Translation of sister-in-law Nglish: Translation of sister-in-law for Spanish speakers Britannica English: Translation of sister-in-law for Arabic speakers

Seen and Heard

What made you want to look up sister-in-law? Please tell us where you read or heard it (including the quote, if possible).

show hide

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

WORD OF THE DAY

besot

play

to fill with foolish love or admiration

Get Word of the Day daily email!

TRENDING NOW

  1. embolization 'the process by which a blood vessel or organ is obstructed by a material mass'

  2. oleaginous 'marked by an offensively ingratiating manner or quality'

  3. pansexual 'sexual desire or attraction...not limited to a particular gender identity or sexual orientation'

  4. symbiote 'an organism living in symbiosis'

  5. charlatan 'faker or fraud'

SEE ALL

BROWSE DICTIONARY

sister-in-law

Test Your Vocabulary

Words Used by Nabokov Quiz

  • image1676440788
  • Choose the best definition or synonym for the word in bold: "There are some eructations that sound like cheers—at least, mine did." Lolita
How Strong Is Your Vocabulary?

Test your vocabulary with our 10-question quiz!

TAKE THE QUIZ
Word Winder's CrossWinder

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Words at Play

image1481409085
9 Words from the Magical Realm

When language is magic

alt-5afefa13cc811
A Field Guide to British Noble Titles

Know your Duchess from your Baroness

image1720821498
7 Words for Bad Endings and Rough Situations

When it doesn't go as planned

alt-5afd9816817c1
Putting the History of 'Limelight' Center Stage

It's, ahem, an illuminating story.

Ask the Editors

video-ghost-words
Ghost Word

The story of an imaginary word that managed to sneak past our editors and enter the dictionary.

image1760257654
2017 Word of the Year: Behind the Scenes

How we chose 'feminism'

video-literally
Literally

How to use a word that (literally) drives some people nuts.

video-his-or-her
Is Singular 'They' a Better Choice?

The awkward case of 'his or her'

Word Games

image1676440788
Words Used by Nabokov Quiz

How familiar are you with Nabokov’s unfamiliar vocabulary?

Take the quiz
cow-coming-home
Farm Idioms Quiz

Not your children's farm quiz.

Take the quiz
How Strong Is Your Vocabulary?
How Strong Is Your Vocabulary?

Test your vocabulary with our 10-question quiz!

Take the quiz
Word Winder's CrossWinder
Word Winder's CrossWinder

A game of winding words.

Play the game