Nouns

Overview

Nouns are classified into two genders ("masculine" and "feminine") and are inflected for number (singular or plural). Adjectives and determiners (articles, demonstratives, possessives, and quantifiers) must be inflected to agree with the noun in gender and number.

Portuguese does not inflect nouns to indicate their grammatical function or case, relying instead on the use of prepositions (simple and phrasal), on pleonastic objects, or on the context or word order.

Gender and number

Most adjectives and demonstratives, and all articles must be inflected according to the gender and number of the noun they reference:

   esta linda casa branca ("this lovely white house")
   este lindo carro branco ("this lovely white car")
   estas lindas aves brancas ("these lovely white birds")
   estes lindos gatos brancos ("these lovely white cats")

Plural formation

Portuguese nouns form their plurals by adding -s if the singular ends in a vowel, and -es if the singular ends in n, r or z. If the singular ends in s, then if the last syllable is stressed, the plural adds -es, and otherwise the plural is the same as the singular. Words ending in m change that m into ns, and words ending in l change that l into -is (e.g. animal > animais). Words ending in ão vary in how they form their plurals: some replace the ão with ães, others with ões, and others just add an -s like the other nouns ending in a vowel.

Gender determination

Grammatical gender of inanimate entities is often different from that used in sister languages: thus, for example, Portuguese árvore ("tree") and flor ("flower") are feminine, while Spanish árbol and Italian fiore are masculine; Portuguese mar ("sea") and mapa ("map") are masculine, while French mer and mappe are feminine.

在许多情况下，名词的性别和数量可以从其词尾推断出来：基本模式是阳性的单数和复数“-o”/“-os”，阴性的单数和复数“-a”/“-as”。因此，casa（“房子”）、mala（“手提箱”）、pedra（“石头”）和intelligênciacarro>（“汽车”）、saco（“包袋”]）、tijolo（“砖”）和aborecisimento（“烦恼”）是阴性的。然而，完整的规则相当复杂：例如，以-ção为词尾的名词通常是阴性的，除了bração（“粗手臂”）等增强词。还有许多异常例外情况。对于以其他字母结尾的单词，几乎没有什么规则：flor（“花”）、gente（“百姓”）、nau（“船”）、1maré（“潮”）是女性化的，而amor（“爱”）、＜i>pente'（“梳子”）、pau（“棍子”）、café（“咖啡”）是阴性的。

On the other hand, the gender of some nouns, as well as of first- and second-person pronouns, is determined semantically by the sex or gender of the referent: aquela estudante é nova, mas aquele estudante é velho ("this (female) student is new, but that (male) student is old"); or eu sou brasileiro ("I am Brazilian", said by a man) and eu sou brasileira (the same, said by a woman).

Also, many animate masculine nouns have specific feminine derivative forms to indicate female sex or social gender: lobo ("wolf" or "male wolf", masculine gender) → loba ("she-wolf", feminine), conde ("count", m.) → condessa ("countess", f.), doutor ("doctor" or "male doctor", m.) → doutora ("female doctor", f.), ator ("actor", m.) → atriz ("actress", f.), etc.