Etymology

fast

F4A1S1T1

Today it means: Firmly or securely fixed in place; stable. Full definition →

First used 9th c.Middle English fast ← Old English fæst ← Proto-West Germanic *fast
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fast · adjective, noun, interjection1

  1. Proto-Germanic*fastuz
  2. Proto-West Germanic*fast
  3. Old Englishfæst
  4. Middle Englishfast
  5. English todayfast

From Middle English fast, fest, from Old English fæst (“firm, secure”), from Proto-West Germanic *fast, from Proto-Germanic *fastuz; see it for cognates and further etymology. The development of “rapid” from an original sense of “secure” apparently happened first in the adverb and then transferred to the adjective; compare hard in expressions like “to run hard”. The original sense of “secure, firm” is now slightly archaic, but retained in the related fasten (“make secure”). Also compare close meaning change from Latin rapiō (“to snatch”) to Latin rapidus (“rapid, quick”), from Irish sciob (“to snatch”) to Irish sciobtha (“quick”).

fast · adverb2

  1. Old English · inherited fromfæste
  2. Middle English · inherited fromfast
  3. English todayfast

From Middle English fast, faste, from Old English fæste, from fæst + -e (adverb-forming suffix).

fast · verb3

  1. Old Norse · derived fromfasta
  2. Proto-Germanic · inherited from*fastijaną“to fasten”
  3. Proto-Germanic · inherited from*fastāną“to fast”
  4. Proto-West Germanic · inherited from*fastēn
  5. Old English · inherited fromfæstan“to fast”
  6. Middle English · inherited fromfasten
  7. English todayfast

From Middle English fasten, from Old English fæstan (“to fast”), from Proto-West Germanic *fastēn, from Proto-Germanic *fastāną (“to fast”), from the same root as Proto-Germanic *fastijaną (“to fasten”), derived from *fastuz, and thereby related to Etymology 1. The religious sense is presumably introduced in the Gothic church, from Gothic 𐍆𐌰𐍃𐍄𐌰𐌽 (fastan, “hold fast (viz. to the rule of abstinence)”). This semantic development is unique to Gothic, the term glosses Greek νηστεύω (nēsteúō), Latin ieiuno which do not have similar connotations of "holding fast". The feminine noun Old High German fasta likely existed in the 8th century (shift to neuter Old High German fasten from the 9th century, whence modern German Fasten). The Old English noun originally had the sense "fortress, enclosure" and takes the religious sense only in late Old English, perhaps influenced by Old Norse fasta. The use for reduced nutrition intake for medical reasons or for weight reduction develops by the mid-1970s, back-formed from the use of the verbal noun fasting in this sense (1960s).

fast · noun4

  1. Old Norse · derived fromfasta“fast, fasting”
  2. Proto-Germanic · inherited from*fastu(b)nją“fast, fasting”
  3. Proto-West Germanic · inherited from*fastuni
  4. Old English · inherited fromfæsten“fast, fasting”
  5. Middle English · inherited fromfaste
  6. English todayfast

From Middle English faste, fasten, from Old English fæsten (“fast, fasting”), from Proto-West Germanic *fastuni, from Proto-Germanic *fastu(b)nją (“fast, fasting”). Cognate with Old Frisian festene, feste (Modern West Frisian fêsten, fêste), Middle Dutch vastene (Modern Dutch vasten), Middle Low German vastene (Modern German Low German Fasten), German Faste, Fasten (“fast, fasting”), Gothic 𐍆𐌰𐍃𐍄𐌿𐌱𐌽𐌹 (fastubni, “fasting”). Possibly merged with Old Norse fasta (“fast, fasting”), whence also Danish faste (“fast, fasting”), Swedish fasta (“fast, fasting”).

FAST · noun, phrase, proper noun, adjective5

Abbreviation. Coined in recognition of the word fast, e.g. (medical sense) describing the need for speedy diagnosis and treatment.

Words from the same roots

Proto-Germanic*fastuz all →

fastness

First known use, by meaning

  • from 9th c. Firmly or securely fixed in place; stable.
  • from 10th c. Steadfast, with unwavering feeling. (Now mostly in set phrases like fast friend(s).)
  • from 14th c. Moving with great speed, or capable of doing so; swift, rapid; light.
  • from 14th c. 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).
  • 16th–19th c. Deep or sound (of sleep); fast asleep (of people).
  • from 17th c. Not running or fading when subjected to detrimental conditions such as wetness or intense light; permanent.
  • from 18th c. Having an extravagant lifestyle or immoral habits.
  • from 19th c. Ahead of the correct time or schedule.

Etymology from Wiktionary, CC BY-SA 4.0.