fast
(dated) Firmly or securely fixed in place; stable.
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)).)
(of a neutron) Having a kinetic energy between 1 million and 20 million electron volts; often used to describe the energy state of free neutrons at the moment of their release by a nuclear fission or nuclear fusion reaction (i.e., before the neutrons have been slowed down by anything).
Of a place, characterised by business, hustle and bustle, etc.
Causing unusual rapidity of play or action.
(of a piece of hardware) Able to transfer data in a short period of time.
(of dyes or colours) Not running or fading when subjected to detrimental conditions such as wetness or intense light; permanent.
(obsolete) Tenacious; retentive.
(dated) Having an extravagant lifestyle or immoral habits.
(ahead) Ahead of the correct time or schedule.
(of photographic film) More sensitive to light than average.
(of a girl or young woman) Uncharacteristically mature or promiscuous for one's age.
(rail transport) A train that calls at only some stations it passes between its origin and destination, typically just the principal stations.
(archery) (nodot=1): {{n-g|a warning not to pass between the arrow and the target.}}
(firmly, securely, tightly, fixedly) In a firm or secure manner, securely; in such a way as not to be moved; safe, sound .
(deeply or soundly, of sleeping) (of sleeping) Deeply or soundly .
(closely following, on someone_s heels) Immediately following in place or time; close, very near .
(quickly) Quickly, with great speed; within a short time .
(ahead of the correct time) Ahead of the correct time or schedule.
To practice religious abstinence, especially from food.
To reduce or limit one's nutrition intake for medical or health reasons, to diet.
(sciences) To cause (a person or animal) to abstain, especially from eating.
The act or practice of fasting, religious abstinence from food.
Any of the fasting periods in the liturgical year.