# acus
## Latin
### Pronunciation

* (Classical Latin) IPA: /ˈa.kus/, [ˈäkʊs̠]
* (modern Italianate Ecclesiastical) IPA: /ˈa.kus/, [ˈäːkus]

### Etymology 1

From Proto-Italic *akus, from Proto-Indo-European *h₂eḱus, from the root *h₂eḱ- (“sharp”). Related to acuō (“sharpen, whet”) and aciēs (“edge”).

#### Noun

acus f (genitive acūs); fourth declension
* a needle, a pin
* bodkin
* Alternative form of acus (“bran”)
** 4 CE – c. 70 CE, Columella, De re rustica 2.14:nam sēmina excussa in āreā jacēbunt, superque eā paulātim eōdem modō reliquī fasciculī excutientur, ac dūrissimae quidem acūs rejectae sēparataeque erunt ā cūdentibus, minūtae vērō, quae dē siliquīs cum fabā resēderint, aliter sēcernentur.

##### Declension

Fourth-declension noun.

##### Derived terms

* acia
* acū pingō
* acū tetigistī
* acuārius
* acūcula
* acula
* aculeus
* acūmen
* acuō
* acupūnctūra
* aquifolium
* foramen acūs
* rem acū tetigistī

##### Descendants

* Aromanian: ac
* Dalmatian: juac
* Istriot: ago
* Italian: ago
* Neapolitan: aco
* Northern-Italo Romance:
** Romagnol: êg m
* Romanian: ac
* Sardinian: àcu

### Etymology 2

From Proto-Italic *akos, from Proto-Indo-European *h₂éḱos (“tip, bristle; ear/blade of grain, awn, chaff”), from the root *h₂eḱ- (“sharp”). Cognates include agna (“ear”) and Proto-Germanic *ahaz (“ear”), Proto-Germanic *aganō, *ahanō (“chaff”) (> English awn), Ancient Greek ἄχυρον (ákhuron) (> Greek άχυρο (áchyro, “hay”)), and Tocharian B āke (“tip, peak, end”).

#### Noun

acus n (genitive aceris); third declension
* bran, awn, chaff
    Synonym: āplūda
** 234 BCE – 149 BCE, Cato the Elder, De agri cultura 54.2:sī fēnum non erit, frondem īligneam et hederāceam datō. paleās trīticeās et hordeāceās, acus fabāginum, viciam, vel dē lupīnō, item dē cēterīs frūgibus omnia condito.
** 116 BCE – 27 BCE, Marcus Terentius Varro, Agricultural Topics 1.52:īs trītīs oportet ē terrā subjectārī vallīs aut ventilābrīs, cum ventus spīrat lēnis. ita fit ut quod levissimum est in eō atque appellātur acus <ac palea> ēvannātur forās extrā āream ac frūmentum, quod est ponderōsum, pūrum veniat ad corbem.
** 116 BCE – 27 BCE, Marcus Terentius Varro, Agricultural Topics 1.57:parietēs et solum opere tēctōriō marmorātō lōrīcandī; sī minus, ex argillā mixtā acere ē frūmentō et amurcā, quod mūrem et vermem nōn patitur esse et grāna facit solidiōra ac firmiōra.
** 116 BCE – 27 BCE, Marcus Terentius Varro, Agricultural Topics 3.9.8:in cubīlibus, cum parturient, acus substernendum.

##### Declension

Third-declension noun (neuter, imparisyllabic non-i-stem).

##### Derived terms

* acerātus
* acerōsus

### References

* 1 2 Wodtko, Dagmar S., Irslinger, Britta, Schneider, Carolin (2008) “*h₂ek̂-”, in Nomina im indogermanischen Lexikon [Nouns in the Indo-European Lexicon] (in German), Heidelberg: Universitätsverlag Winter, pages 287–300
* ↑ De Vaan, Michiel (2008) “acu-”, in Etymological Dictionary of Latin and the other Italic Languages (Leiden Indo-European Etymological Dictionary Series; 7), Leiden, Boston: Brill, →ISBN, page 23
* ↑ De Vaan, Michiel (2008) “acus, -eris”, in Etymological Dictionary of Latin and the other Italic Languages (Leiden Indo-European Etymological Dictionary Series; 7), Leiden, Boston: Brill, →ISBN, pages 23-4

### Further reading

* Ernout, Alfred, Meillet, Antoine (1985) “acus”, in Dictionnaire étymologique de la langue latine: histoire des mots‎ (in French), 4th edition, with additions and corrections of Jacques André, Paris: Klincksieck, published 2001, page 7
* “acus”, in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
* “acus”, in Charlton T. Lewis (1891) An Elementary Latin Dictionary, New York: Harper & Brothers
* "acus", in Charles du Fresne du Cange’s Glossarium Mediæ et Infimæ Latinitatis (augmented edition with additions by D. P. Carpenterius, Adelungius and others, edited by Léopold Favre, 1883–1887)
* acus in Gaffiot, Félix (1934) Dictionnaire illustré latin-français, Hachette.
* Carl Meißner, Henry William Auden (1894) Latin Phrase-Book‎, London: Macmillan and Co. you have hit the nail on the head: rem acu tetigisti
* “acus”, in Harry Thurston Peck, editor (1898), Harper's Dictionary of Classical Antiquities, New York: Harper & Brothers
* “acus”, in William Smith et al., editor (1890), A Dictionary of Greek and Roman Antiquities, London: William Wayte. G. E. Marindin

## Old Dutch
### Etymology

From Proto-West Germanic *akusi.

### Noun

acus f
* axe

#### Descendants

* Middle Dutch: ākes, āex
** Dutch: aks, akst
** Limburgish: aaks

### References

* “akkus”, in Oudnederlands Woordenboek, 2012