See also: Actio



From āctum +‎ -tiō, using the supine of agō (do, make).



āctiō f (genitive āctiōnis); third declension

  1. action; a doing or performing, behavior
  2. public function, civil act
  3. (law) suit, process, action
  4. gesticulation made while speaking
  5. (drama) the action, plot, series of events


Third-declension noun.

Case Singular Plural
Nominative āctiō āctiōnēs
Genitive āctiōnis āctiōnum
Dative āctiōnī āctiōnibus
Accusative āctiōnem āctiōnēs
Ablative āctiōne āctiōnibus
Vocative āctiō āctiōnēs

Related termsEdit



  • actio in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
  • actio in Charlton T. Lewis (1891) An Elementary Latin Dictionary, New York: Harper & Brothers
  • actio 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)
  • actio in Gaffiot, Félix (1934) Dictionnaire illustré Latin-Français, Hachette
  • Carl Meißner; Henry William Auden (1894) Latin Phrase-Book[1], London: Macmillan and Co.
    • practical philosophy: philosophia, quae in actione versatur
    • the treatment of the piece: actio
    • delivery: actio (Brut. 38)
    • the delivery is rather halting, poor: actio paulum claudicat
    • a private, civil prosecution: actio, petitio
  • actio in Harry Thurston Peck, editor (1898) Harper's Dictionary of Classical Antiquities, New York: Harper & Brothers
  • actio in William Smith et al., editor (1890) A Dictionary of Greek and Roman Antiquities, London: William Wayte. G. E. Marindin



act +‎ -io



actio (first-person singular present actiaf)

  1. to act



Welsh mutation
radical soft nasal h-prothesis
actio unchanged unchanged hactio
Note: Some of these forms may be hypothetical. Not every
possible mutated form of every word actually occurs.

Further readingEdit

  • R. J. Thomas, G. A. Bevan, P. J. Donovan, A. Hawke et al., editors (1950–present), “actio”, in Geiriadur Prifysgol Cymru Online (in Welsh), University of Wales Centre for Advanced Welsh & Celtic Studies