§134. Declension of Cardinals and Ordinals

Of the Cardinals only ūnus, duo, trēs, the hundreds above one hundred, and mīlle when used as a noun, are declinable.

a. For the declension of ūnus, see § 113. It often has the meaning of same or only. The plural is used in this sense; but also, as a simple numeral, to agree with a plural noun of a singular meaning: as, ūna castra, one camp (cf. § 137. b). The plural occurs also in the phrase ūnī et alterī, one party and the other (the ones and the others).

b. Duo,¹ two, and trēs, three, are thus declined:—

c. The hundreds, up to 1000, are adjectives of the First and Second Declensions, and are regularly declined like the plural of bonus.

d. Mīlle, a thousand, is in the singular an indeclinable adjective:—

• mīlle modīs, in a thousand ways.
• cum mīlle hominibus, with a thousand men.
• mīlle trahēns variōs colōrēs (Aen. 4.701), drawing out a thousand various colors.

In the plural it is used as a neuter noun, and is declined like the plural of sedīle (§ 69): mīlia, mīlium, mīlibus, etc.

e. The ordinals are adjectives of the First and Second Declensions, and are regularly declined like bonus.