Alternative formsEdit


From Proto-Italic *feiljos (the Latin can reflect either one, but Faliscan fīleo, hīleo points to *fīl-), from Proto-Indo-European *dʰeh₁ylios (sucker), a derivation from the verbal root *dʰeh₁(y)- (to suck). Related to fēmina, fellō, fētus, Old English delu (nipple, teat), dēon (to suck, suckle), Old Armenian դալ (dal). More at doe.



fīlius m (genitive fīliī or fīlī, feminine fīlia); second declension

  1. a son
    Ubi est noster filius?
    Where is our son?
    • Caecilius Statius (died ca. 168 BC); in: Scaenicae romanorum poesis fragmenta secundis curis. Volumen II. Comicorum fragmenta. – Comicorum romanorum praeter Plautum et Terentium fragmenta secundis curis, edited by Otto Ribbeck, Leipzig, 1873, page 48:
      Fílius meus ín me incedit [éccum] sat hilará schema.
    • Caecilius Statius (died ca. 168 BC); in: Remains of Old Latin, edited and translated by E. H. Warmington, vol. I, 1935, page 496f.:
      Priscianus, ap. G.L., II, 199, 17, K: 'Schema' pro 'schemate.' . . . Caecilius in Hypobolimaeo–
      . . . filius . . . in me incedit satis
      hilara schema.
      Aged peasant, guardian of the changeling Chaerestratus:
      Priscianus: 'Schema' for 'schemate.' . . . Caecilius in The Changeling
      Here comes my son towards me in merry shape.
  2. (by extension) any male descendant
  3. (in the plural) children


Second-declension noun.

Case Singular Plural
Nominative fīlius fīliī
Genitive fīliī
Dative fīliō fīliīs
Accusative fīlium fīliōs
Ablative fīliō fīliīs
Vocative fīlī fīliī

1Found in older Latin (until the Augustan Age).


Derived termsEdit



  • filius in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
  • filius in Charlton T. Lewis (1891) An Elementary Latin Dictionary, New York: Harper & Brothers
  • filius 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)
  • filius in Gaffiot, Félix (1934) Dictionnaire illustré Latin-Français, Hachette