Merriam-Webster Logo
SINCE 1828
Menu
×

An Encyclopædia Britannica Company

See What's Trending Now See More Trending Words

brother-in-law

play
noun broth·er-in-law \ ˈbrə-t͟hər-ən-ˌlȯ , ˈbrət͟h-rən- , ˈbrə-t͟hərn- \

Definition of brother-in-law

plural brothers-in-law play \ˈbrə-t͟hərz-ən-\
1 :the brother of one's spouse
2 a :the husband of one's sibling
b :the husband of one's spouse's sibling

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

See brother-in-law defined for kids

People Are Reading

alt-59c2960017c94
The Ambiguity of Pushing 'Up' and 'Back'
alt-59c2cb9e9ef54
Trending: Ivanka: "An 'Otherwise' Incredible Day"
image536372841
Every Letter Is Silent, Sometimes
video-title-words-of-the-year-1066
Words of the Year: 1066

First Known Use of brother-in-law

14th century

BROTHER-IN-LAW Defined for English Language Learners

brother-in-law

play
noun

Definition of brother-in-law for English Language Learners

  • : the brother of your husband or wife

  • : the husband of your sister

BROTHER-IN-LAW Defined for Kids

brother-in-law

noun broth·er-in-law \ ˈbrə-t͟hər-ən-ˌlȯ \

Definition of brother-in-law for Students

plural brothers-in-law
1 :the brother of a person's husband or wife
2 :the husband of a person's sister

Learn More about brother-in-law

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

Seen and Heard

What made you want to look up brother-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

holus-bolus

play

all at once

Get Word of the Day daily email!

TRENDING NOW

  1. otherwise "in other respects"

  2. federalism Graham says bill gives power to states

  3. bodega "Don’t mess with the beloved bodega."

  4. carceral Of, relating to, or suggesting a jail or prison

  5. allegory No spoilers!

SEE ALL

BROWSE DICTIONARY

brother-in-law

Test Your Vocabulary

Challenging Vocabulary Quiz Returns!

  • stylized-drawing-of-woman-pole-vaulting-across-gap-to-get-trophy
  • Which is a synonym of fuliginous?
Spell It

Can you spell these 10 commonly misspelled words?

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

alt-59c2960017c94
The Ambiguity of Pushing 'Up' and 'Back'

When you push a meeting, where does it go?

image536372841
Silent Letters

When each letter can be seen but not heard

alt-59c17b8172892
'So Long': A Common But Mysterious Goodbye

Its origins are surprisingly murky.

alt-59c13729150dc
"Immune to" or "Immune from"?

Nobody is immune to this question.

Ask the Editors

video-title-words-of-the-year-1066
Words of the Year: 1066

Or, Why Pig Meat is Called 'Pork' and Cow Meat is Called 'Beef'

payday
How Often Is 'Biweekly'?

Don't get us started on 'bimonthly'

video-irregardless-grammar-peeve-blend-of-the-synonyms-irrespective-and-regardless
Irregardless

It is in fact a real word (but that doesn't mean you should use it).

video-moose-goose-weird-plurals
Weird Plurals

One goose, two geese. One moose, two... moose. What's up with that?

Word Games

stylized-drawing-of-woman-pole-vaulting-across-gap-to-get-trophy
Challenging Vocabulary Quiz Returns!

No tricks, just difficult words.

Take the quiz
name-that-color-logo
Name that Color!

NEW! Additional colors! More obscure than before!

Take the quiz
Spell It
Spell It

Can you spell these 10 commonly misspelled words?

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

A game of winding words.

Play the game