Merriam-Webster Logo
SINCE 1828
Menu
×

An Encyclopædia Britannica Company

See What's Trending Now See More Trending Words

dos

variants: or do's

Definition of dos

Explore M-W

alt-59e8af1b31525
Trending: NY Times: Trump's Call Ignites 'Imbroglio'
alt-59ea52ed7b96f
Learned Fools: On Names for Students
tycoon
17 English Words that Come From Japanese
video-title-words-of-the-year-1066
Words of the Year: 1066

DOS

abbreviation

Definition of DOS

disk operating system

Medical Dictionary

dos

abbreviation

medical Definition of dos

dosage

Learn More about dos

  1. Spanish Central: Translation of dos

Seen and Heard

What made you want to look up dos? 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

nuncupative

play

spoken rather than written

Get Word of the Day daily email!

TRENDING NOW

  1. imbroglio "a public scandal"

  2. spurious of a deceitful nature or quality

  3. righteous We provide an assortment of definitions

  4. Kafkaesque 'A nightmarish quality'

  5. mike "microphone"

SEE ALL

BROWSE DICTIONARY

Test Your Vocabulary

The Exceptions Quiz III

  • one-green-toy-robot-amidst-many-red-toy-robots
  • Which of these words does not mean "nonsense"?
True or False

Test your knowledge - and maybe learn something along the way.

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-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'

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

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
True or False
True or False?

Test your knowledge - and maybe learn something along the way.

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

A game of winding words.

Play the game