Etymologically
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acus

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Pronunciation

  • IPA (Classical): [ˈa.kʊs][1]
  • IPA (Ecclesiastical): [ˈaː.kus][1]

Forms

acus f (genitive acūs); fourth declension[1]

Etymology

It goes back to the root Proto-Indo-European *h₂eḱ- (“sharp”).[1][2] The NIL takes it as directly inherited from Proto-Indo-European *h₂eḱus (“pointed”), while de Vaan argues that the noun is a later Latin formation from the same root.[1] It is related to ācer “sharp” and acuō “to sharpen”.[2][1]

Earliest recorded meaning

The OLD's first examples are from the Moretum and Cicero, who speaks of a wound that seems to have been made with a needle.[2][3] Köbler dates Cicero 81–43 BC.[4]

Semantic evolution

It was a needle or pin, used for sewing and as an ornament, and a hairpin, acū pingere “to paint with the needle” meant to embroider.[2][3] The proverb rem acū tangere “to touch the thing with a needle” meant to hit the nail on the head.[5] Pliny uses it of the pipefish or garfish, also called belonē.[2][3] Isidore explains acūs as pins that hold a woman's hair together.[6]

Köbler records acus nautica “compass needle” in later Latin.[4] Its diminutive acicula gave English acicular “needle-shaped”, and the noun survives in Italian ago and Romanian ac.[7][1]

Timeline

  • 81–43 BC – Cicero speaks of a wound made as if by a needle.[3][4]
  • 43 BC–18 AD – Ovid uses acū pingere of embroidery.[5][4]
  • 23/24–79 AD – Pliny the Elder uses it of the pipefish.[2][4]
  • 1794 – English acicular is recorded.[7]

Meanings

Noun

  1. A needle, pin, acū pingere, to embroider.[2][3]
  2. A hairpin.[2]
  3. A pipefish or garfish.[2][3]
  4. (plural) Husks, chaff.[2]

Word family

  • acuārius
  • acūcula
  • acula
  • aculeus
  • acupūnctūra

Usage notes

A different neuter noun acus (genitive aceris) “husks, chaff”, found in Cato and Varro, is the word de Vaan treats, from Proto-Italic *akos (“sharpness”).[8][2][5]

References

  1. ^ a b c d e f g Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ a b c d e f g h i j k Glare, P. G. W., ed. (2012), Oxford Latin Dictionary, 2nd ed., Oxford: Oxford University Press
  3. ^ a b c d e f Lewis, Charlton T.; Short, Charles (1879), A Latin Dictionary, Oxford: Clarendon Press
  4. ^ a b c d e Köbler, Gerhard (2010), Lateinisches Abkunfts- und Wirkungswörterbuch für Altertum und Mittelalter, online ed., koeblergerhard.de
  5. ^ a b c Gaffiot, Félix (2016), Dictionnaire latin-français, new ed. by Gérard Gréco et al. (Gaffiot 2016), online ed.
  6. ^ Isidore of Seville, Etymologiarum sive Originum libri XX, ed. W. M. Lindsay (Oxford, 1911).
  7. ^ a b Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
  8. ^ de Vaan, Michiel (2008), Etymological Dictionary of Latin and the other Italic Languages, Leiden Indo-European Etymological Dictionary Series 7, Leiden; Boston: Brill