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fast 1

adj. fast·er, fast·est
1. Acting, moving, or capable of acting or moving quickly; swift.
a. Accomplished in relatively little time: a fast visit.
b. Acquired quickly with little effort and sometimes unscrupulously: made a fast buck scalping tickets.
3. Quick to understand or learn; mentally agile: a class for the faster students.
4. Indicating a time somewhat ahead of the actual time: The clock is fast.
5. Allowing rapid movement or action: a fast running track.
6. Designed for or compatible with a short exposure time: fast film.
a. Disposed to dissipation; wild: ran with a fast crowd.
b. Flouting conventional moral standards; sexually promiscuous.
8. Resistant, as to destruction or fading: fast colors.
9. Firmly fixed or fastened: a fast grip.
10. Fixed firmly in place; secure: shutters that are fast against the rain.
11. Lasting; permanent: fast rules and regulations.
12. Deep; sound: in a fast sleep.
adv. faster, fastest
1. In a secure manner; tightly: hold fast.
2. To a sound degree; deeply: fast asleep.
3. In a rapid manner; quickly.
4. In quick succession: New ideas followed fast.
5. Ahead of the correct or expected time: a watch that runs fast.
6. In a dissipated, immoderate way: living fast.
7. Archaic Close by; near.
fast friend
A friend who is firm in loyalty: became fast friends after only knowing each other a few months.

[Middle English, from Old English fæst, firm, fixed; see past- in Indo-European roots.]
Synonyms: fast1, rapid, swift, fleet2, speedy, quick, expeditious
These adjectives refer to something marked by great speed. Fast and rapid are often used interchangeably, though fast is more often applied to the person or thing in motion, and rapid to the activity or movement involved: a fast runner; rapid strides. Swift suggests smoothness and sureness of movement (a swift current), and fleet, lightness of movement (The cheetah is the fleetest of animals). Speedy refers to velocity (a speedy train) or to promptness or hurry (a speedy resolution to the problem). Quick most often applies to what takes little time or to what is prompt: a quick snack; your quick reaction. Expeditious suggests rapid efficiency: sent the package by the most expeditious means. See Also Synonyms at faithful.

fast 2

intr.v. fast·ed, fast·ing, fasts
1. To abstain from food.
2. To eat very little or abstain from certain foods, especially as a religious discipline.
1. The act or practice of abstaining from or eating very little food.
2. A period of such abstention or self-denial.

[Middle English fasten, from Old English fæstan; see past- in Indo-European roots.]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adv.1.fastest - most quicklyfastest - most quickly        
References in classic literature ?
The Mongolia plied regularly between Brindisi and Bombay via the Suez Canal, and was one of the fastest steamers belonging to the company, always making more than ten knots an hour between Brindisi and Suez, and nine and a half between Suez and Bombay.
The ostrich runneth faster than the fastest horse, but it also thrusteth its head heavily into the heavy earth: thus is it with the man who cannot yet fly.
He did not wait to question, but in an instant a guard was racing to the nearest dock and though the air was thin and almost gone at the rooftop they managed to launch the fastest one-man, air-scout machine that the skill of Barsoom had ever produced.
All the time, our overfraught hearts are beating at a rate that would far outstrip the fastest gallop of the fastest horses ever foaled.
I marched the Expedition down the steep and tedious mule-path and took up as good a position as I could upon the middle of the glacier--because Baedeker said the middle part travels the fastest.
The louder she screamed, the harder he whipped; and where the blood ran fastest, there he whipped longest.
Very well,' said she; and they set out: and as Frederick walked the fastest, he left his wife some way behind.
He travels the fastest who travels alone,'" she quoted at him.
Smith says she is one of the fastest launches on the river, and that if he had had another man to help him with the engines we should never have caught her.
Or was he a cynical bachelor crow, believing that he travels the fastest who travels alone?
Having told you as much as that, I do not think I am asking too much if I ask you for my clothes and dressing-case, and for the fastest motor-car you can furnish me with.
As soon as the vessel discovered the galleys she went about with the object and in the hope of making her escape by her speed; but the attempt failed, for the chief galley was one of the fastest vessels afloat, and overhauled her so rapidly that they on board the brigantine saw clearly there was no possibility of escaping, and the rais therefore would have had them drop their oars and give themselves up so as not to provoke the captain in command of our galleys to anger.