A one-termination adjective uses the same nominative singular form with masculine, feminine, and neuter nouns. Thus prūdēns can describe a prudent man, woman, or plan. The adjective still has three genders: “one termination” means one visible nominative singular ending, not the absence of gender agreement.
The genitive is indispensable because it reveals the stem: prūdēns, prūdentis; audāx, audācis; fēlīx, fēlīcis. Most members take several i-stem endings, but this class contains genuine lexical exceptions. Unless otherwise labeled, the forms and composed examples below represent unmarked Classical prose.
One nominative, three genders
| Head noun | Gender and case | Phrase | Translation |
|---|---|---|---|
| vir | masculine nominative singular | vir prūdēns | a prudent man |
| fēmina | feminine nominative singular | fēmina prūdēns | a prudent woman |
| cōnsilium | neuter nominative singular | cōnsilium prūdēns | a prudent plan |
Vir prūdēns antequam respondet rem tōtam cōnsīderat.
A prudent man considers the whole matter before answering.
Fēmina prūdēns pecūniam ad tempora difficilia servāvit.
A prudent woman saved money for difficult times.
Cōnsilium prūdēns multōs cīvēs servāre potest.
A prudent plan can save many citizens.
English also leaves “prudent” unchanged, but the resemblance ends after the nominative singular. Latin prūdentem, prūdentī, and prūdentia mark relations that English normally expresses by position or prepositions.
Recovering the stem
Remove genitive singular -is to obtain the working stem:
| Dictionary entry | Stem | What the nominative conceals | Meaning |
|---|---|---|---|
| prūdēns, prūdentis | prūdent- | t disappears before nominative -s | prudent |
| audāx, audācis | audāc- | c + s is written x | bold |
| fēlīx, fēlīcis | fēlīc- | c + s is written x | fortunate |
| ingēns, ingentis | ingent- | t disappears before -s | huge |
| vetus, veteris | veter- | an older s-stem alternation | old |
The changes are historical sound patterns, not freely chosen spelling rules. You may predict audācem once you know audācis, but the nominative audāx alone does not tell you whether the stem vowel is long. Likewise, vetus must be learned with veteris; a guessed stem vetus- will produce nonexistent forms.
Nūntius audāx per castra hostium nocte cucurrit.
A bold messenger ran through the enemy camp at night.
Nūntium audācem dux statim laudāvit.
The commander immediately praised the bold messenger.
This minimal pair exposes the change from nominative audāx to accusative audācem. English changes only word order; Latin changes the adjective and noun to mark their role.
The practical paradigm of prūdēns
The following is the regular i-stem-like paradigm used by many one-termination adjectives.
| Case | Masculine/Feminine singular | Neuter singular | Masculine/Feminine plural | Neuter plural |
|---|---|---|---|---|
| Nominative | prūdēns | prūdēns | prūdentēs | prūdentia |
| Genitive | prūdentis | prūdentis | prūdentium | prūdentium |
| Dative | prūdentī | prūdentī | prūdentibus | prūdentibus |
| Accusative | prūdentem | prūdēns | prūdentēs (also prūdentīs) | prūdentia |
| Ablative | prūdentī | prūdentī | prūdentibus | prūdentibus |
| Vocative | prūdēns | prūdēns | prūdentēs | prūdentia |
The nominative and accusative neuter singular remain prūdēns; the neuter plural is prūdentia. Masculine/feminine accusative singular prūdentem is therefore a useful gender diagnostic. As with other i-stems, accusative plural -īs is Classical and especially visible in conservative editions alongside -ēs.
Iūdex testī prūdentī crēdidit.
The judge trusted the prudent witness.
Haec verba prūdentia omnēs audīre dēbent.
Everyone ought to hear these prudent words.
In testī prūdentī, both words are dative singular, though testī could be masculine or feminine from form alone. In verba prūdentia, neuter plural agreement identifies prūdentia. Do not translate first and then guess: parse the possible forms, locate the head, and let syntax resolve ambiguity.
Agreement and placement
One termination in the nominative does not weaken agreement elsewhere. The adjective still copies gender, number, and case from its head noun, whether attributive or predicative.
Dux mīlitī fēlīcī praemium dedit.
The commander gave a reward to the fortunate soldier.
Urbs post tam longum bellum fēlīx vidētur.
The city seems fortunate after such a long war.
The first fēlīcī is masculine dative singular and stands attributively with mīlitī. The second fēlīx is feminine nominative singular and is predicative with urbs. The nominative form itself does not reveal the gender; the head noun does.
Placement can change information structure without changing dependency. Compare the following:
Rēgem cōpia ingēns mīlitum nōn servāvit.
A huge force of soldiers did not save the king.
Cōpia mīlitum ingēns erat, sed exercitus sine frūmentō manēbat.
The force of soldiers was huge, but the army remained without grain.
In both sentences feminine nominative ingēns belongs with cōpia, not with nearby genitive plural mīlitum. The second order places the size as more salient predicate information. Latin order guides focus; the agreement relation survives the separation.
Where the regular i-stem pattern stops
Most one-termination adjectives use ablative singular -ī, genitive plural -ium, and neuter plural -ia, but this is not a perfectly uniform class. Vetus, veteris is a consonant stem: ablative vetere, genitive plural veterum, neuter plural vetera. Pauper, pauperis regularly has ablative paupere; substantival forms often favor consonant-stem behavior. Several words, including dīves, prīnceps, and particeps, have lexical combinations of -e and genitive plural -um that must be checked in a dictionary.
Present participles in -ns add a functional contrast. Used adjectivally, they normally have ablative -ī; used verbally, especially in an ablative absolute, they normally have -e: ab amantī mātre “by a loving mother” but mātre vigilante “while the mother was keeping watch.” This is a real Classical distinction, not a spelling preference. Poetry can extend or suppress i-stem endings (literary).
There is no honest shortcut that predicts every exception from the nominative. Learn common adjectives with their genitive and, when necessary, their ablative and genitive plural. The full system is organized on i-stem adjective endings.
Parsing and production diagnostics
For a visible form such as audācis, list its possibilities before translating: genitive singular of any gender, or nominative/accusative plural -īs only if the quantity and stem support that analysis in an unmacronized text. Then identify government and agreement. For production:
- Retrieve the genitive and stem.
- Determine the head noun’s gender, number, and case.
- Choose the regular ending or a memorized lexical exception.
- Check that separation and nearby nouns have not distracted you from the true head.
Common Mistakes
1. Inventing a special neuter nominative for a one-termination adjective.
❌ Cōnsilium prūdente est.
Incorrect — the nominative neuter singular is prūdēns, the same as masculine and feminine.
✅ Cōnsilium prūdēns est.
The plan is prudent.
2. Building oblique forms from the nominative rather than the genitive stem.
❌ Dux nūntium audāxem laudāvit.
Incorrect — audāx has the stem audāc-, revealed by audācis.
✅ Dux nūntium audācem laudāvit.
The commander praised the bold messenger.
3. Matching a separated adjective to the nearest noun.
❌ Cōpia mīlitum ingentium erat.
Incorrect for the force was huge — ingentium would modify genitive plural mīlitum.
✅ Cōpia mīlitum ingēns erat.
The force of soldiers was huge.
4. Forcing regular i-stem endings onto vetus.
❌ Dē bellō veterī senex nārrāvit.
Incorrect in the regular Classical paradigm of vetus — its ablative is vetere.
✅ Dē bellō vetere senex nārrāvit.
The old man told a story about an ancient war.
Key Takeaways
One-termination adjectives have one nominative singular across all genders, but full agreement remains active. The genitive reveals the stem, the head noun reveals the gender, and syntax reveals the case. Most members show -ī, -ium, and neuter -ia; common exceptions such as vetus prove why dictionary forms matter more than a guessed visual pattern.
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