Nouns wanting in the Plural
Some nouns are ordinarily found in the Singular number only (singulria tantum). These are
1. Most proper names: as, Caesar, Csar; Gallia, Gaul.
2. Names of things not counted, but reckoned in mass: as, aurum, gold; r, air; trticum, wheat.
3. Abstract nouns: as, ambiti, ambition; fortitd, courage; calor, heat. [p. 41]
Many of these nouns, however, are used in the plural in some other sense.
The plural of a proper name may be applied to two or more persons or places, or even things, and so become strictly common:
duodecim Caesars, the twelve Csars.
Galliae, the two Gauls (Cis- and Transalpine).
Castores, Castor and Pollux; Iovs, images of Jupiter.
The plural of names of things reckoned in mass may denote particular objects: as, aera, bronze utensils, nivs, snowflakes; or different kinds of a thing: as, ers, airs (good and bad).
The plural of abstract nouns denotes occasions or instances of the quality, or the like:
quaedam excellentiae, some cases of superiority; tia, periods of rest; calrs, frgora, times of heat and cold.
Nouns wanting in the Singular
Some nouns are commonly or exclusively found in the Plural (plrlia tantum). Such are
1. Many names of towns: as, Athnae (Athens), Thri, Philipp, Vi.
2. Names of festivals and games: as, Olympia, the Olympic Games; Bacchnlia, feast of Bacchus; Qunqutrs, festival of Minerva; ld Rmn, the Roman Games.
3. Names of classes: as, optimts, the upper classes; mirs, ancestors; lber, children; pents, household gods; Quirts, citizens (of Rome).
4. Words plural by signification: as, arma, weapons; arts, joints; dvitiae, riches; sclae, stairs; valvae, folding-doors; fors, double-doors; angustiae, a narrow pass (narrows); moenia, city walls.
NOTE 1.Some words, plural by signification in Latin, are translated by English nouns in the singular number: as, dliciae, delight, darling; faucs, throat; fids, lyre (also singular in poetry); nsidiae, ambush; cervcs, neck; viscera, flesh.
NOTE 2.The poets often use the plural number for the singular, sometimes for metrical reasons, sometimes from a mere fashion: as, ra (for s), the face; scptra (for scptrum), sceptre; silentia (for silentium), silence.
Some nouns of the above classes ( 101. 1-4), have a corresponding singular, as noun or adjective, often in a special sense:
1. As noun, to denote a single object: as, Bacchnal, a spot sacred to Bacchus; optims, an aristocrat.
2. As adjective: as, Cat Mior, Cato the Elder.
3. In a sense rare, or found only in early Latin: as, scla, a ladder, valva, a door; artus, a joint.
Nouns Defective in Certain Cases
Many nouns are defective in case-forms:
Indeclinable nouns, used only as nominative and accusative singular: fs, nefs, nstar, nihil, opus (need), secus.
NOTE 1.The indeclinable adjective necesse is used as a nominative or accusative.
NOTE 2.The genitive nihil and the ablative nihil (from nihilum, nothing) occur.
Nouns found in one case only (monoptotes):
1. In the nominative singular: gls (F.).
2. In the genitive singular: dicis, nauc (N.).
3. In the dative singular: dvsu (M.) (cf. 94. c).
4. In the accusative singular: amussim (M.); vnum (dative vn in Tacitus).
5. In the ablative singular: pond (N.); mne (N.); ast (M.), by craft; iuss, iniuss, nt, and many other verbal nouns in -us (M.) ( 94. c).
NOTE.Mne is also used as an indeclinable accusative, and an old form mn is used as ablative. Pond with a numeral is often apparently equivalent to pounds. A nominative singular astus and a plural asts occur rarely in later writers.
6. In the accusative plural: nfitis.
Nouns found in two cases only (diptotes):
1. In the nominative and ablative singular: fors, forte (F.).
2. In the genitive and ablative singular: spontis (rare), sponte (F.).
3. In the accusative singular and plural: dicam, dics (F.).
4. In the accusative and ablative plural: fors, fors (F.) (cf. fors), used as adverbs.
Nouns found in three cases only (triptotes):
1. In the nominative, accusative, and ablative singular: impetus, -um, - (M.)
50 ; lus, -em, - (F.).
2. In the nominative, accusative, and dative or ablative plural: grts, -ibus (F).
3. In the nominative, genitive, and dative or ablative plural: igera, -um, -ibus (N.); but igerum, etc., in the singular (cf. 105. b).
Nouns found in four cases only (tetraptotes):
In the genitive, dative, accusative, ablative singular: dicinis, -, -em, -e (F.).
Nouns declined regularly in the plural, but defective in the singular:
1. Nouns found in the singular, in genitive, dative, accusative, ablative: frgis, -, -em, -e (F.); opis, - (once only), -em, -e (F.; nominative Ops as a divinity).
2. Nouns found in the dative, accusative, ablative: prec, -em, -e (F.).
3. Nouns found in the accusative and ablative: cassem, -e (F.); sordem, -e (F.).
4. Nouns found in the ablative only: ambge (F.); fauce (F.); obice (C.).
Nouns regular in the singular, defective in the plural: [p. 43]
1. The following neuters have in the plural the nominative and accusative only: fel (fella), far (farra), hordeum (hordea), is, broth (ira), mel (mella), murmur (murmura), ps (pra), rs (rra), ts or ths (tra).
NOTE.The neuter is, right, has only ira in classical writers, but a very rare genitive plural irum occurs in old Latin.
2. calx, cor, cs, crux, fax, faex, lanx, lx, nex, s (ris),
51 os (ossis),
52 px, pix, rs, sl, sl, vas (vadis), want the genitive plural.
3. Most nouns of the fifth declension want the whole or part of the plural (see 98. a).
Nouns defective in both singular and plural:
1. Noun found in the genitive, accusative, ablative singular; nominative, accusative, dative, ablative plural: vicis, -em, -e; -s, -ibus.
2. Noun found in the genitive, dative, accusative, and ablative singular; genitive plural wanting: dapis, -, -em, -e; -s, -ibus.