Editing: Fourth Declension Nouns in Latin

Make changes to the article content below. You can preview your changes or see a diff comparing to the original text.

5,417 characters

# 1. Essentials at a Glance 
Fourth Declension nouns in Latin grammar generally feature a stem ending in *-u-* and a genitive singular in *-ūs*. Most are masculine and end in *-us* in the nominative (e.g. **frūctus**, “fruit”) while a handful are feminine (e.g. **manus**, “hand”) or neuter (e.g. **cornū**, “horn”). They occur frequently in literary, historical, and legal texts. Mastery of these forms is essential for accurate reading and translation, as they appear in both concrete and abstract vocabulary.

---

# 2. Definition & Importance
The **Fourth Declension in Latin grammar** comprises nouns typically marked by **-us** or **-ū** endings, with the genitive singular **-ūs**. These words include everyday terms like *domus* (“house”) and *manus* (“hand”), as well as abstract nouns like *impetus* (“attack”) or *metus* (“fear”).

Understanding the **Latin Fourth Declension examples** is crucial for correct syntax, morphology, and reading comprehension. Frequent words like *senātus* (“Senate”) and *exercitus* (“army”) highlight its importance in historical and political contexts. Recognizing **common errors in the Fourth Declension**—such as confusing its genitive (-ūs) with the second declension (-ī)—helps learners avoid misinterpretations in classical texts.

---

# 3. Forms & Morphology
Below are two standard paradigms illustrating the **Fourth Declension forms**. Most masculine/feminine nouns use an *-us* nominative, while neuters end in *-ū*.

| Case            | M./F. (frūctus, “fruit”) | Neuter (cornū, “horn”) |
|-----------------|---------------------------|-------------------------|
| **Nom. Sg.**    | frūctus                  | cornū                  |
| **Gen. Sg.**    | frūctūs                  | cornūs                 |
| **Dat. Sg.**    | frūctuī                  | cornū                  |
| **Acc. Sg.**    | frūctum                  | cornū                  |
| **Abl. Sg.**    | frūctū                   | cornū                  |
| **Nom. Pl.**    | frūctūs                  | cornua                 |
| **Gen. Pl.**    | frūctuum                 | cornuum                |
| **Dat./Abl. Pl.** | frūctibus (rarely -ubus) | cornibus              |
| **Acc. Pl.**    | frūctūs                  | cornua                 |

**Key notes**:
- A few nouns (e.g. **domus**, “house”) exhibit **mixed** forms (sometimes borrowing endings from the second declension).
- Feminine nouns include **manus** (“hand”) and **porticus** (“portico”).
- Neuter nouns like **cornū** and **genū** have plural endings in **-ua** (cornua, genua).
- Some words allow **-ubus** in the dative/ablative plural (e.g. **arcubus**, “to/with bows”) instead of **-ibus**.

---

# 4. Usage & Examples
Fourth Declension nouns follow normal Latin case rules. They commonly denote concrete items, actions/results of verbs (e.g. *cursus* from **currere**, “to run”), or collective bodies (e.g. *senātus*).

**1.** *Cicero: “Habēmus senātūs cōnsultum...”*  
   - *“We have a decree of the Senate...”*  
   - **senātūs** (gen. sg.) modifies *cōnsultum* (“decree”), emphasizing the Senate’s authority.

**2.** *Caesar: “Ad dextrum cornū profectus...”*  
   - *“Having set out to the right wing...”*  
   - **cornū** (acc. sg. neuter) = “wing” of the army; literally “horn.”

**3.** *Horace (Odes): “... gelūque flūmina cōnstitērint acūtō.”*  
   - *“... and the rivers have frozen solid with sharp frost.”*  
   - **gelū** (abl. of means) = “by/with frost.”

**4.** *Livy: “Prīmō impetū urbem capere cōnātī sunt.”*  
   - *“They tried to capture the city in the first assault.”*  
   - **impetū** (abl. sg.) = “by/with an attack.”

**5.** *Tacitus: “Nē iniussū Caesaris discēderent.”*  
   - *“That they not depart without Caesar’s command.”*  
   - **iussū** (abl. sg. meaning “by order”) is found mostly in this fixed ablative form.

---

# 5. Common Pitfalls
- **Mistaking Endings**: Confusing fourth declension **-ūs** with second declension **-ī**. Check context and macrons carefully.  
- **Domus Variations**: *Domus* mixes forms from the second and fourth declensions (e.g. *domī* “at home,” *domum* “(to) home,” *domō* “from home”).  
- **Gender Errors**: Words like *manus* or *porticus* are feminine despite their *-us* ending.  
- **Plural vs. Genitive Overlap**: *-ūs* can be either a plural nominative/accusative or a genitive singular (e.g. *senātūs*). Context is key.

---

# 6. Additional Notes & Nuances
Fourth Declension nouns are often **verbal derivatives**, expressing actions or results (*impetus*, *cantus*, *cursus*). Some form part of **idiomatic phrases**—such as *manūs dare* (“to surrender”) or *manūs cōnserere* (“to join battle”).

A few exhibit **archaic or poetic** forms in early Latin (e.g. genitive *-ī* for *senātī*). Poets also favor them for their **long -ū** endings, which fit certain meters. Rarely, alternative endings like **-ubus** appear for the dative/ablative plural (e.g. *arcubus*, *lacubus*).

---

# 7. Key Takeaways
- **Recognize -ūs** endings: These signal the **fourth declension** (gen. sg. or nom./acc. pl.).  
- **Memorize irregulars**: Especially *domus* and the feminine nouns (e.g. *manus*).  
- **Watch for neuter -ū**: Plural in **-ua** (e.g. *cornua*).  
- **Check context**: Many forms overlap. Use surrounding words (adjectives, prepositions) to clarify.  
- **Beware special ablatives** (*iussū*, *nātū*, *iniussū*), often used adverbially.

Document Structure

H11. Essentials at a Glance
H12. Definition & Importance
H13. Forms & Morphology
H14. Usage & Examples
H15. Common Pitfalls
H16. Additional Notes & Nuances
H17. Key Takeaways

Markdown Help

# Heading 1Main Title

## Heading 2Section Title

**bold text**Bold Text

*italic text*Italic Text

[Link](https://...)Hyperlink

1. ItemNumbered List

- ItemBullet List