Third Declension Triple-Termination Adjectives

Adjectives of the third declension have either one, two or three gendered endings.

  • Triple-termination: ācer, ācris, ācre (sharp)
  • Twin-termination: levis (m/f), leve (light)
  • Single-termination: …these are complicated. I’ll address them in a coming post

Triple-Termination Formation

Triple-Termination Third Declension Adjectives are declined as follows:

Here are additional triple-declensions thirds to practice declining:

  • alacer, alacris, alacre: lively, cheerful
  • campester, campestris, campestre: flat
  • celeber, celebris, celebre: famed, crowded
  • equester, equestris, equestre: equestrian
  • palūster, palūstris, palūstre: boggy
  • pedester, pedestris, pedestre: pedestrian, ordinary
  • puter, putris, putre: rotting
  • salūber, salūbris, salūbre: healthy
  • silvester, silvestris, silvestre: woodland
  • terrester, terrestris, terrestre: terrestrial
  • volucer, volucris, volucre: aerial
  • octōber, octōbris, ocrōbre: of October
  • (likewise with all menstrual [monthly] adjectives)

Do note: the triple-termination design was developed relatively late, so you may encounter some or all of these adjectives as twin-termination adjectives, with either the masculine or the feminine representing either the masculine or the feminine in early Latin prose and poetry [e.g. homō alacris or fēmina alacer would be acceptable] (AG, 115 n1)

Also, celer, celeris, celere (swift) is an odd bird.

The Essential AG: 115-115a