fast

1a : firmly fixed roots fast in the ground

b : tightly shut the drawers were fast

c : adhering firmly The boards were fast a few hours after being glued together.

d : not easily freed : stuck a ball fast in the mouth of the cannon

e : stable movable items were made fast to the deck

2 : firmly loyal became fast friends

3a : characterized by quick motion, operation, or effect:

(1) : moving or able to move rapidly : swift a fast horse

(2) : taking a comparatively short time a fast race

(3) : imparting quickness of motion a fast bowler

(4) : accomplished quickly fast work

(5) : agile of mind especially : quick to learn a class for fast students

b : conducive to rapidity of play or action a fast track

c(1) of a timepiece or weighing device : indicating in advance of what is correct Your clock is two minutes fast.

(2) : according to or being daylight saving time

d : contributing to a shortening of exposure time fast film

e : acquired with unusually little effort and often by shady or dishonest methods had a keen eye for a fast buck— R. A. Keith

4a : securely attached a rope fast to the wharf

b : tenacious a fast hold on her purse

5a archaic : sound asleep

b of sleep : not easily disturbed fell into a fast sleep

6 : not fading or changing color readily fast colors

7a : actively seeking excitement and pleasure : wild a pretty fast crowd

b : sexually promiscuous

8 : resistant to change (as from destructive action or fading) fast dyes —often used in combination sunfastacid-fast bacteria

Definition of fast