1099. The singular of a word denoting a person is sometimes used in a
collective sense.
This singular is generally a military designation: as, #mīles#, #eques#,
#pedes#, #hostis#, #Rōmānus#, #Poenus#. But other substantives and
adjectives are occasionally thus used.
1100. A substantive or adjective denoting a person is often used in the
singular as representative of a class, particularly when two persons are
contrasted: as,
#sī tabulam dē naufrāgiō stultus adripuerit, extorquēbitne eam sapiēns?#
_Off._ 3, 89, _if a fool has seized a plank from a wreck, will the sage
twitch it away?_
1101. The neuter singular of certain adjectives is used as an abstract
substantive.
These adjectives have commonly stems in #-o-#, and are often used in the
partitive genitive (1250). The nominative is rare, also the accusative
and ablative, except in prepositional constructions. Such are: #bonum#,
#malum#; #rēctum#, #prāvum#; #decōrum#, #indecōrum#; #honestum#;
#vērum#, #falsum#; #iūstum#, #iniūstum#; #aequum#; #ambiguum#;
#rīdiculum#. #ūtile#, #ināne#, #commūne#, #īnsīgne#, #simile#, &c.
1102. Certain adjectives, which originally agreed with an appellative
denoting a thing, have dropped the appellative and become substantives.
Such are: #Āfricus#, sc. #ventus#; #Āfrica#, sc. #terra#; #calda#, sc.
#aqua#; #cānī# sc. #capillī#; #circēnsēs#, sc. #lūdī#; #decuma#, sc.
#pars#; #fera#, sc. #bēstia#; #hīberna#, sc. #castra#; #merum#, sc.
#vīnum#; #nātālis#, sc. #diēs#; #patria#, sc. #terra#; #praetexta#, sc.
#toga#; #summa#, sc. #rēs#; #trirēmis#, sc. #nāvis#, and many others.
1103. Certain adjectives denoting relationship, friendship, hostility,
connection, or age, may be used in both numbers as substantives.
Such are: (_a._) #adfīnis#, #cōgnātus#, #cōnsanguineus#, #gentīlis#,
#necessārius#, #propīnquus#; (_b._) #adversārius#, #amīcus#, #inimīcus#,
#familiāris#, #hostis#, #intimus#, #invidus#, #socius#, #sodālis#;
(_c._) #contubernālis#, #manipulāris#, #vīcīnus#; (_d._) #adulēscēns#,
#aequālis#, #iuvenis#, #senex#.
1104. The masculine plural of many adjectives is used substantively to
denote a class.
Such are: #bonī#, _the good_, _the well-disposed_, _conservatives_,
_patriots_, _our party_; #improbī#, _the wicked_, _the dangerous
classes_, _revolutionists_, _anarchists_, _the opposite party_; #doctī#,
#indoctī#; #piī#, #impiī#, and the like.
1105. Proper names of men are used in the plural to denote different
persons of the same name, or as appellatives to express character,
oftenest good character: as,
#duo Metellī, Celer et Nepōs#, _Br._ 247, _the two Metelluses, Celer and
Nepos_. #quid Crassōs, quid Pompēiōs ēvertit?# J. 10, 108, _what
overthrew a Crassus, Pompey what?_ i.e. men like Crassus and Pompey.
1106. The neuter plural of adjectives of all degrees of comparison is
very often used as a substantive.
Such adjectives are usually in the nominative or accusative, and may
have a pronoun, a numeral, or an adjective, agreeing with them. In
English the singular is often preferred. Such are: #bona#, #mala#;
#vēra#, #falsa#; #haec#, _this_; #omnia#, _everything_; #haec omnia#,
_all this_, &c., &c.
1107. Names of countries are sometimes used in the plural when the
country consists of several parts which are called by the same name as
the whole country: as, #Galliae#, _the Gauls_; #Germāniae#, _the
Germanies_.
1108. Material substantives are often used in the plural to denote
different sorts of the substance designated, its constituent parts, or
objects made of it: as,
#aera#, _lumps of bronze_, _bronzes_, _coppers_. #aquae#, _water in
different places_, _medicinal springs_. #cērae#, _pieces of wax_,
_tablets_, _wax masks_, _waxworks_. #marmora#, _kinds of marble_,
_blocks of marble_, _works of marble_. #nivēs#, _snowflakes_,
_snowdrifts_, _snowstorms_, _repeated snows_. #spūmae#, _masses of
foam_. #sulpura#, _lumps of sulphur_. #vīna#, _wines_, _different kinds
of wine_.
1109. Abstract substantives are often used in the plural to denote
different kinds or instances of the abstract idea, or an abstract idea
pertaining to several persons or things: as,
#sunt domesticae fortitūdinēs nōn īnferiōrēs mīlitāribus#, _Off._ 1, 78,
_there are cases of heroism in civil life fully equal to those in war_.
#tē cōnscientiae stimulant maleficiōrum tuōrum#, _Par._ 18, _you are
tormented by pricks of conscience for your sins_. #propter siccitātēs
palūdum#, 4, 38, 2, _because the swamps were dry everywhere_.
1110. The plural is sometimes used in generalizations, and in poetry to
magnify a single thing, to give mystery to the statement, or often
merely for metrical convenience: as, #advēnisse familiārēs dīcitō#, Pl.
_Am._ 353, _say that the people of the house are come_, the plural
#familiārēs# denoting one person. #Priamī dum rēgna manēbant#, V. 2, 22,
_while Priam’s realms still stood_. #externōs optāte ducēs#, V. 8, 503,
_choose captains from a foreign strand_, i.e. Aeneas.