SINCE 1828

An Encyclopædia Britannica Company

mood disorder

noun

Definition of mood disorder

:any of several psychological disorders (such as major depressive disorder or bipolar disorder) characterized by abnormalities of emotional state — called also affective disorder

First Known Use of mood disorder

1969

Medical Dictionary

mood disorder

noun

medical Definition of mood disorder

:any of several psychological disorders characterized by abnormalities of emotional state and including especially major depressive disorder, dysthymia, and bipolar disorder — called also affective disorder

Learn More about mood disorder

See words that rhyme with mood disorder

Seen and Heard

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

show

WORD OF THE DAY

nuncupative

play

spoken rather than written

BROWSE DICTIONARY

Test Your Vocabulary

The Exceptions Quiz III

Which of these words does not mean "nonsense"?

Name That Thing

Test your visual vocabulary with our 10-question challenge!

TAKE THE QUIZ

Word Winder's CrossWinder

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

TAKE THE QUIZ

Words at Play

alt-59ea52ed7b96f

Learned Fools: On Names for Students

Where did we get 'freshman' and 'sophomore'?

alt-59e900afadac6

The Synonyms 'Discover' and 'Invent'

In the past, you could invent fruit.

alt-59e8c3440f453

I'll Have the Us(ual)

Shortening 'usual': easy to say, hard to spell

alt-59e77dc36c593

The Origins of 'Lobbyist'

From the front hallways to the back rooms

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'

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

one-green-toy-robot-amidst-many-red-toy-robots

The Exceptions Quiz III

Which of these things doesn't belong?

Take the quiz

knupfer-painting-solon-before-croesus

Forms of Government Quiz

Name that government! Or something like that.

Take the quiz

Name That Thing

Name That Thing

Test your visual vocabulary with our 10-question challenge!

Take the quiz

Word Winder's CrossWinder

Word Winder's CrossWinder

A game of winding words.

Play the game