1. Proper names; as, Cicerō, Cicero; Italia, Italy.
2. Nouns denoting material; as, aes, copper; lac, milk.
3. Abstract nouns; as, ignōrantia, ignorance; bonitās, goodness.
4. But the above classes of words are sometimes used in the Plural. Thus:—
a) Proper names,—to denote different members of a family, or specimens of a type; as, Cicerōnēs, the Ciceros; Catōnēs, men like Cato.
b) Names of materials,—to denote objects made of the material, or different kinds of the substance; as, aera, bronzes (i.e. bronze figures); ligna, woods.
c) Abstract nouns,—to denote instances of the quality; as, ignōrantiae, cases of ignorance.
Nouns used in the Plural only.
[56]. Here belong—
1. Many geographical names; as, Thēbae, Thebes; Leuctra, Leuctra; Pompejī, Pompeii.
2. Many names of festivals; as, Megalēsia, the Megalesian festival.
3. Many special words, of which the following are the most important:—