In Portuguese, ordinal numbers describe the order of a noun. Thus, it is considered an adjective and must agree in gender and number with the noun. Here are the ordinal numbers from 1 to 10.
| um, uma | 1 | primeiro, primeira | 1.o / 1.a |
| dois, duas | 2 | segundo, segunda | 2.o / 2.a |
| três | 3 | terceiro, terceira | 3.o / 3.a |
| quatro | 4 | quarto, quarta | 4.o / 4.a |
| cinco | 5 | quinto, quinta | 5.o / 5.a |
| seis | 6 | sexto, sexta | 6.o / 6.a |
| sete | 7 | sétimo, sétima | 7.o / 7.a |
| oito | 8 | oitavo, oitava | 8.o / 8.a |
| nove | 9 | nono, nona | 9.o / 9.a |
| dez | 10 | décimo, décima | 10.o / 10.a |
Abbreviation of Ordinal Numbers
The ordinal numbers are abbreviated as follows:
Feminine: cardinal number + “ . ” + “ a ,” e.g., “primeira” (1.a), “quarta” (4.a), “nona” (9.a).
Masculine: cardinal number + “ . ” + “ o ,” e.g., “primeiro” (1.o), “quarto” (4.o), “nono” (9.o).
Describing Dates in Portuguese
Unlike in English, where dates are described using ordinal numbers, e.g., “the 24th of October,” dates are expressed using cardinal numbers in Portuguese, e.g., “24 de outubro.”
A notable exception is the first day of the month, in which case the ordinal number is used, e.g., “primeiro de novembro.”
Fractional Numbers
Fractional numbers from fourth to tenth are the same as the ordinal number, e.g., “um quarto dos jogadores” (a fourth of the players), “um quinto dos recursos” (a fifth of the resources).
To describe the fractional number 1/2 (half), we use the adjective “meio” (masculine) or “meia” (feminine), e.g., “meio quilo” (half a kilo), “meia hora” (half an hour), “meio caminho” (half way), etc.
We also use the feminine noun “metade” to describe half the quantity of something, and it is often followed by “de,” e.g., “a metade da terra” (half of the land).
The main difference that you need to remember to distinguish between “meio” and “metade” is that the former is often an adjective, e.g., “meio quilo” (half a kilo). In contrast, the latter is always a noun, e.g., “a metade da aula” (half of the class).
The fractional number 1/3 (third) is “terço” (not terceiro), e.g., “um terço da população” (a third of the population).
The “um” can be dropped before 1/2 if preceded by an integer, e.g., 1 ½ (um e meio).
We cover higher ordinal numbers and fractions in Level VI, Lesson 1.
Other lessons in Level II:
