1. Third Declension Adjectives
Chapter 16:
Third Declension Adjectives

2. Third Declension Adjectives
So far, we’ve learned the group of adjectives known as 1st/2nd declension adjectives (e.g. magnus, a, um or pulcher, pulchra, pulchrum)
The other major group of adjectives is known as the 3rd declension adjectives, and they decline like 3rd-declension i-stem nouns.

3. Review: Third Declension i-Stems
M/F Sing
M/F Pl
N Sing
N Pl
Nom
civis
cives
animal
animalia
Gen
civium
animalis
animalium
Dat
civi
civibus
animali
animalibus
Acc
civem
Abl
cive

4. Third Declension Adjectives
3rd declension adjectives decline just like that, except that they have –i as the ending for the ablative singular in all genders.
So:
Abl sing (all genders) = -i
Gen pl (all genders) = -ium
Nom/Acc pl (neuters) = -ia

5. Third Declension Adjectives
We divide up adjectives from this group into three categories.
The only difference between these categories is in the nominative singular: adjectives can have
Three forms (one for each gender)
Two forms (one for M&F, one for N)
One form (one for all three genders)
We call these different categories 3-ending, 2-ending, and 1-ending adjectives, for obvious reasons.

6. Third Declension Adjectives
3-ending adjectives
ex: acer, acris, acre sharp, keen
celer, celeris, celere swift, quick
2-ending adjectives (the largest category)
ex: fortis, forte strong, brave
dulcis, dulce sweet
1-ending adjectives
ex: potens, gen potentis powerful
senex, gen senis old, aged

7. Third Declension Adjectives
Just like 1st/2nd declension adjectives can be used to describe nouns of any declension, 3rd declension adjectives can be used to describe nouns of any declension. Ex: fortis rex, ingens porta
Remember nouns and adjectives must agree in GENDER, NUMBER, and CASE!

8. Third Declension Adjectives
The stem of 3-ending adjectives can be found by looking at the F or N form
ex: acer, acris, acre: stem = acr-
celer, celeris, celere: stem = celer-
For 1-ending adjectives, Wheelock gives you the genitive form in the vocabulary entry.