Definition

/fɑːst/

noun

A train that calls at only some stations it passes between its origin and destination, typically just the principal stations

adjective

Firmly or securely fixed in place; stable.
“That rope is dangerously loose. Make it fast!”
Firm against attack; fortified by nature or art; impregnable; strong.
(of people) Steadfast, with unwavering feeling. (Now mostly in set phrases like fast friend(s).)
Moving with great speed, or capable of doing so; swift, rapid.
“I am going to buy a fast car.”
Causing unusual rapidity of play or action.
“a fast billiard table”

adverb

In a firm or secure manner, securely; in such a way as not to be moved; safe, sound .
“Hold this rope as fast as you can.”
(of sleeping) Deeply or soundly .
“He is fast asleep.”
Immediately following in place or time; close, very near .
“Fast by the sturdy batsman the ball unheeded sped. / That ain't my style, said Casey. Strike one, the umpire said.”
Quickly, with great speed; within a short time .
“Do it as fast as you can.”
Ahead of the correct time or schedule.
“I think my watch is running fast.”