U

fasting

verb (used without object)

to abstain from all food.
to eat only sparingly or of certain kinds of food, especially as a religious observance.

verb (used with object)

to cause to abstain entirely from or limit food; put on a fast: to fast a patient for a day before surgery.

noun

an abstinence from food, or a limiting of one’s food, especially when voluntary and as a religious observance; fasting.
a day or period of fasting.

adjective

acting or moving or capable of acting or moving quickly; swift
accomplished in or lasting a short timefast work; a fast visit
(prenominal) adapted to or facilitating rapid movementthe fast lane of a motorway
requiring rapidity of action or movementa fast sport
(of a clock, etc) indicating a time in advance of the correct time
given to an active dissipated life
of or characteristic of such activitya fast life
not easily moved; firmly fixed; secure
firmly fastened, secured, or shut
steadfast; constant (esp in the phrase fast friends)
sport (of a playing surface, running track, etc) conducive to rapid speed, as of a ball used on it or of competitors playing or racing on it
that will not fade or change colour readilya fast dye
1. proof against fadingthe colour is fast to sunlight
2. (in combination)washfast
photog
1. requiring a relatively short time of exposure to produce a given densitya fast film
2. permitting a short exposure timea fast shutter
cricket (of a bowler) characteristically delivering the ball rapidly
informal glib or unreliable; deceptivea fast talker
archaic sound; deepa fast sleep
informal a deceptive or unscrupulous trick (esp in the phrase pull a fast one)
fast worker a person who achieves results quickly, esp in seductions

adverb

quickly; rapidly
soundly; deeplyfast asleep
firmly; tightly
in quick succession
in advance of the correct timemy watch is running fast
in a reckless or dissipated way
fast by or fast beside archaic close or hard by; very near
play fast and loose informal to behave in an insincere or unreliable manner

interjection

archery (said by the field captain to archers) stop shooting!

verb

(intr) to abstain from eating all or certain foods or meals, esp as a religious observance

noun

1. an act or period of fasting
2. (as modifier)a fast day

adj.

Old English fæst “firmly fixed, steadfast, secure, enclosed,” probably from Proto-Germanic *fastuz (cf. Old Frisian fest, Old Norse fastr, Dutch vast, German fest), from PIE root *past- “firm” (cf. Sanskrit pastyam “dwelling place”).

The adverb meaning “quickly, swiftly” was perhaps in Old English, or from Old Norse fast, either way developing from the sense of “firmly, strongly, vigorously” (cf. to run hard means to run fast; also compare fast asleep), or perhaps from the notion of a runner who “sticks” close to whatever he is chasing.

The sense of “living an unrestrained life” (usually of women) is from 1746 (fast living is from 1745). Fast buck recorded from 1947; fast food is first attested 1951. Fast-forward first recorded 1948. Fast lane is by 1966; the fast track originally was in horse-racing (1934); figurative sense by 1960s. To fast talk someone (v.) is recorded by 1946.

Old English fæstan “to fast” (as a religious duty), from Proto-Germanic *fastejan (cf. Old Frisian festia, Old High German fasten, German fasten, Old Norse fasta), from the same root as fast (adj.).

The original meaning was “hold firmly,” and the sense evolution is via “firm control of oneself,” to “holding to observance” (cf. Gothic fastan “to keep, observe,” also “to fast”). Presumably the whole group is a Germanic translation of Medieval Latin observare “to fast.” Related: Fasted; fasting.

Old English fæstan, festen, or Old Norse fasta; from the root of fast (v.).

In addition to the idioms beginning with fast

fast and furious
fast and loose
fast buck
fast lane
fast track

also see:

get nowhere (fast)
hard and fast
pull a fast one
stand one’s ground (fast)
thick and fast