Merriam-Webster Logo
SINCE 1828
Menu
×

An Encyclopædia Britannica Company

left brain

noun

Definition of left brain

  1. :  the left cerebral hemisphere of the human brain especially when viewed in terms of its predominant thought processes (such as analytic and logical thinking)

left–brained

play \ˈleft-ˈbrānd\ adjective

Explore M-W

video-title-words-of-the-year-1066
Words of the Year: 1066
alt-59760690a61d7
Trending: Trump Tweets, We Define: 'Beleaguered'
alt-59775cb5d7779
Words We're Watching: 'Aquafaba'
emoji-the-quiz
The Emoji Quiz

First Known Use of left brain

1827

Medical Dictionary

left brain

noun

Medical Definition of left brain

  1. :  the left cerebral hemisphere of the human brain especially when viewed in terms of its predominant thought processes (as analytic and logical thinking)

left–brained

\ˈleft-ˈbrānd\play adjective

Seen and Heard

What made you want to look up left brain? 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

akimbo

play

set in a bent position

Get Word of the Day daily email!

TRENDING NOW

  1. beleaguer 'Being subjected to constant or repeated trouble or harassment'

  2. scaramouch A new White House communications director

  3. non sequitur “It does not follow”

  4. admiral's mast A massive search ends with an 'admiral's mast'.

  5. calumny 'An untrue statement that is made to damage someone's reputation'

SEE ALL

BROWSE DICTIONARY

left brain

Test Your Vocabulary

The Emoji Quiz

  • emoji-the-quiz
  • What phase of the moon is this: 🌖 ?
Name That Thing

Test your visual vocabulary with our 10-question challenge!

TAKE THE QUIZ
SCRABBLE® Sprint

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-59775cb5d7779
Words We're Watching: 'Aquafaba'

Don't dump out the bean water just yet...

image1358596246
Words About Word Play

Don't just eat your words—play with them!

alt-596f95fe451e7
'Drought' & 'Drouth' Take Us Back In Time

A variant spelling with a long history

alt-59721dd897313
The 'Best' Way to Sign Off On An E-mail

Give them your best

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

emoji-the-quiz
The Emoji Quiz

Think you’re an emoji 👓 expert? Let’s see 🤔

Take the quiz
image941935269
A Game of Thrones Word Quiz

In the Game of Thrones quiz, you learn some new vocabulary. (It’s quite safe, really. You will not die.)

Take the quiz
Name That Thing
Name That Thing

Test your visual vocabulary with our 10-question challenge!

Take the quiz
SCRABBLE® Sprint
SCRABBLE® Sprint

SCRABBLE® fans, sharpen your skills!

Play the game