down

WordReference Random House Learner's Dictionary of American English © 2015

down¹ /daʊn/ adv. 

1. from higher to lower;
   toward or into a lower position or level:
   Tell him to come down.
2. on or to the ground, floor, or the like:
   to fall down.
3. to or in a sitting or lying position:
   Sit down next to her.
4. to an area or district considered lower from a geographical standpoint, esp. southward:
   We drove down to San Diego from Los Angeles.
5. to a lower value, level, or rate:
   Slow down.
6. to a lesser pitch or volume:
   Turn down the radio.
7. in or to a calmer or less active state:
   The wind died down.
8. from an earlier to a later time:
   the history of the church from the Middle Ages down to the present.
9. from a greater to a lesser strength, amount, etc.:
   to water down a drink.
10. earnestly:
    to get down to work.
11. on paper:
    Write this down.
12. in cash at the time of purchase:
    $50 down and $20 a month thereafter.
13. to the point of defeat or submission:
    shouted down the opposition.
14. to the source or actual position:
    to track someone down.
15. into a condition of ill health:
    He came down with the flu.
16. in or into a lower status or condition:
    He was kept down by lack of education.

prep. 

in a descending direction on or along; in a place moved farther away than:

They ran off down the street.

adj. 

[before a noun] directed downward;
going down:

Take the down escalator on the left.

[be/seem + ~] sad; gloomy;
depressed:

You seem pretty down today.

[be + ~] sick and in bed:

He's down with a bad cold.

Sport [be + ~] behind an opponent or opponents in points:

We're down by twenty points.

[be + ~] having lost the amount indicated, esp. at gambling:

After that last race I'm only down $10.

finished or taken care of:

Five down and one to go.

[be + ~] out of order:

The computer is down again.

[Slang.]

• admired:
  a down dude.

n. [countable]

a turn for the worse; reverse:

It was another down for the company already in debt.

Sport [countable] [Football.] one of a series of four plays during which a team must advance the ball at least 10 yd. (9 m) to keep possession of it:

On that last series of downs the team moved the ball well.

v. [~ + object]

to knock, throw, or bring down:

He downed his opponent with a quick right to the jaw.

to drink down, esp. quickly:

I downed the vodka in one gulp.

Informal Terms to defeat in a game or contest:

The Rangers downed the Flyers 2-0 last night.

interj. 

(used as a command or warning) get down:

Down in front, please (= Please sit down in front, so people behind you can see).

idiom

Idioms down cold or pat, learned perfectly:
He always has his facts down cold before he argues with anyone.
Idioms down in the mouth, discouraged; sad;
depressed:
He looks down in the mouth today.
down on, [~ + object] hostile to:
Most of the party's regular members are down on his candidacy.
Idioms down with, [~ + object] (used in a command or a wish, without a subject) to remove from power or do away with:
Down with the king!

down² /daʊn/ n. [uncountable]

1. Clothing the short, soft feathers of some birds, used for filling in clothing for warmth.
2. Botany fine, soft, short hair, such as on plants.

adj. [before a noun]

Clothing filled with down:

a down jacket.