acus

Latin

Etymology

From Proto-Indo-European *h₂eḱ- ‎(“sharp”). Related to acuō ‎(“sharpen, whet”) and aciēs ‎(“edge”).

Pronunciation

• (Classical) IPA^(key): /ˈa.kʊs/

Noun

acus f ‎(genitive acūs); fourth declension

1. a needle, a pin
2. bodkin

Inflection

Fourth declension.

Case	Singular	Plural
nominative	acus	acūs
genitive	acūs	acuum
dative	acuī	acibus
accusative	acum	acūs
ablative	acū	acibus
vocative	acus	acūs

Derived terms

Terms derived from acus

• acia
• acuārius
• acucula
• acula

• aculeus
• acuō
• acū pingō ‎(“I embroider”)

• aquifolium
• foramen acūs ‎(“the eye of a needle”)
• rem acū tetigistī, acū tetigistī

Descendants

• Aromanian: ac
• Dalmatian: juac
• English: acupuncture
• French: aiguille
• Istriot: ago

• Italian: ago
• Romanian: ac
• Sardinian: àcu
• Vulgar Latin: *acūcla (see there for further descendants)

References

• acus in Charlton T. Lewis & 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, 1883–1887)
• acus in Félix Gaffiot (1934), Dictionnaire Illustré Latin-Français, Paris: Hachette.
• Meissner, Carl; Auden, Henry William (1894) Latin Phrase-Book^[1], 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