Etymologically

Etymology and origin of the Proto-Germanic word *fastuz

Confidence
Probable
Ultimate origin
Proto-Indo-European *peh₂ǵ-,*steh₂-
Etymology tree
inherited borrowed derived
Proto-Indo-European *peh₂ǵ-
Ancient Greek πήγνυμι (pḗgnumi)
Proto-Germanic *fastuz
Old Norse fastr
Proto-West Germanic *fast
German fest
Old English fæst
English fast
Proto-West Germanic *fastī
Dutch vast
From the same root
German feststellen ← fest
English breakfast ← fast

Reconstruction

The adjective is *fastuz in Wiktionary[1] and the u-stem *fastu- in Kroonen.[2] Orel writes it as the a-stem *fastaz,[3] Heidermanns as *fasta-,[4] and Köbler gives *fasta-, *fastja- and *fastu- side by side.[5]

Etymology

Kroonen traces it to a PIE root *pHst-, which he analyses as a compound from Proto-Indo-European *peh₂ǵ- (“to become firm”) + *steh₂- (“to stand”), *ph₂ǵ-sth₂-, with the ǵ lost in the heavy cluster.[2]

Morphology

Kroonen takes it as a u-stem that was remodelled into a ja-stem in West Germanic.[2] De Vries also derives Old Norse fastr from *fastu-.[6] Heidermanns rejects the u-stem: the East Norse participle meaning "promised", which Noreen and others cited for *fastu-, is in his view the past participle of the verb for "to fasten".[4] The West Germanic forms show both types: Old Saxon fast beside Old Saxon festi, and Old High German fast beside Old High German festi.[2][7]

Evidence

The adjective is attested in North and West Germanic: Old Norse fastr, Old English fæst, Old Frisian fest, Old Saxon fast and Old High German festi.[2] Heidermanns calls it common Germanic, attested in Gothic only indirectly;[4] Gothic has the verb 𐍆𐌰𐍃𐍄𐌰𐌽 (fastan, “to hold, to keep, to fast”) and the compound 𐍅𐌹𐍄𐍉𐌳𐌰𐍆𐌰𐍃𐍄𐌴𐌹𐍃 (witodafasteis, “lawyer”).[8] Orel adds a Burgundian *fastis.[3] Outside Germanic, Kroonen and Orel match it with Old Armenian հաստ (hast, “firm”).[2][3]

Competing analyses

Kroonen rules out a PIE *post-, which would not have given the Armenian form, and so abandons the connection with Sanskrit पस्त्य (pastyá, “homestead”).[2] That Sanskrit word, "dwelling", is the usual comparison according to de Vries,[6] and Wiktionary keeps it as possible, with a PIE *pastV- "solid, stable".[1] Orel derives the word from *po-stH-o- "standing firm", built on Proto-Indo-European *stā- (“to stand, to set”).[3]

Orel explains the sense "to fast" of the verb *fastēnan as a calque of Latin iēiūnium observāre (“to observe a fast”), after Wessén and Velten,[3] and Lehmann reports the same view with its critics;[8] Seebold separates the verb for "to fast" from the adjective altogether and gives it its own etymology.[4]

Meanings

  1. firm, solid[2][5]
  2. fixed, secure[1]

Old Norse also used the adjective for "hard, strong",[6] and Old Frisian for "reliable" and "honourable".[9]

Derivatives

  • *fastāną "to observe, to hold firm to; to fast",[10] Kroonen's *fastēn-;[2] with the noun *fastubniją "observance; fasting".[11]
  • *fastijaną "to fasten".[12]
  • *fastulīkaz "solid, firm",[13] Orel's *fasta-līkaz.[3]
  • *erþōfastuz "fixed to the ground",[14] Orel's *erþa-fastaz.[3]
  • In Orel: *fastinōjanan "to fasten, to pledge" and *fastīn "firmness".[3]

Reflexes

  • Gothic: no adjective; the verb 𐍆𐌰𐍃𐍄𐌰𐌽 (fastan, “to hold, to keep, to fast”)[8][4]
  • Old Norse: fastr (“firm, hard, strong”)[6]
  • Old English: fæst (“firm, strong, secure”)[15]
  • Old Frisian: fest (“firm, secure, reliable”)[9]
  • Old Saxon: fast (“firm, constant, secure”), festi[16]
  • Old High German: fast (“firm, strong”), festi[7][2]

References

  1. ^ a b c Wiktionary, the free dictionary, https://en.wiktionary.org, p. s.v. *fastuz
  2. ^ a b c d e f g h i j Kroonen, Guus (2013), Etymological Dictionary of Proto-Germanic, Leiden Indo-European Etymological Dictionary Series 11, Leiden / Boston: Brill, p. 131
  3. ^ a b c d e f g h Orel, Vladimir (2003), A Handbook of Germanic Etymology, Leiden / Boston: Brill, p. s.v. *fastaz
  4. ^ a b c d e Heidermanns, Frank (1993), Etymologisches Wörterbuch der germanischen Primäradjektive, Berlin / New York: De Gruyter, p. s.v. fasta-
  5. ^ a b Köbler, Gerhard (2014), Germanisches Wörterbuch, 5th ed., online, koeblergerhard.de/wikiling, p. s.v. *fasta-
  6. ^ a b c d de Vries, Jan (1977), Altnordisches etymologisches Wörterbuch, 2nd ed., Leiden: Brill, p. s.v. fastr
  7. ^ a b Köbler, Gerhard (2014), Althochdeutsches Wörterbuch, 6th ed., online, koeblergerhard.de/wikiling, p. s.v. fast
  8. ^ a b c Lehmann, Winfred P. (1986), A Gothic Etymological Dictionary, based on the third edition of Vergleichendes Wörterbuch der gotischen Sprache by Sigmund Feist, Leiden: Brill, p. s.v. fastan
  9. ^ a b Hofmann, Dietrich; Popkema, Anne Tjerk (2008), Altfriesisches Handwörterbuch, Heidelberg: Carl Winter, p. s.v. fest
  10. ^ Wiktionary, the free dictionary, https://en.wiktionary.org, p. s.v. *fastāną
  11. ^ Wiktionary, the free dictionary, https://en.wiktionary.org, p. s.v. *fastubniją
  12. ^ Wiktionary, the free dictionary, https://en.wiktionary.org, p. s.v. *fastijaną
  13. ^ Wiktionary, the free dictionary, https://en.wiktionary.org, p. s.v. *fastulīkaz
  14. ^ Wiktionary, the free dictionary, https://en.wiktionary.org, p. s.v. *erþōfastuz
  15. ^ Köbler, Gerhard (2014), Altenglisches Wörterbuch, 4th ed., online, koeblergerhard.de/wikiling, p. s.v. fæst
  16. ^ Köbler, Gerhard (2014), Altsächsisches Wörterbuch, 5th ed., online, koeblergerhard.de/wikiling, p. s.v. fast

Related etymologies

  • *stainaz · also from Proto-Indo-European
  • *beraną · also from Proto-Indo-European
  • *fadēr · also from Proto-Indo-European
  • *watōr · also from Proto-Indo-European
  • *ga- · also from Proto-Indo-European
  • *frijaz · also from Proto-Indo-European
  • *fallaną · also from Proto-Indo-European
  • *standaną · also from Proto-Indo-European
Cite this entry

“*fastuz.” Etymologically, 16 Nov. 2026, etymologically.com/gem-pro/*fastuz. Accessed 16 Nov. 2026.

Last edited on . ·