Spanish nouns

The Spanish language has nouns that express concrete objects, groups and classes of objects, qualities, feelings and other abstractions. All nouns have a conventional grammatical gender. Countable nouns inflect for number (singular and plural). However, the division between uncountable and countable nouns is more ambiguous than in English.

All Spanish nouns have one of two grammatical genders: masculine and feminine (mostly conventional, that is, arbitrarily assigned). Most adjectives and pronouns, and all articles and participles, indicate the gender of the noun they reference or modify.

In a sentence like "Large tables are nicer", the Spanish equivalent, Las mesas grandes son más bonitas, must use words according to the gender of the noun. The noun, mesa ("table"), is feminine in Spanish. Therefore, the article must be feminine too, and so la instead of el, is required. However, mesas is plural here, so we need las rather than la. The two adjectives, whether next to the noun or after the verb, have to "agree" with the noun as well. Grande is a word which is invariable for gender, so it just takes a plural marker: grandes. Bonito is a word that can agree for both gender and number, so we say bonitas to go with mesas. A student of Spanish must keep in mind all these features when making sentences.

In general, most nouns that end in -a, -ción / -sión and -ad are feminine; the rest of the nouns, which usually end in -o or a consonant, are masculine.

Nouns can be grouped in the following categories:

Nouns ending in -o are masculine, with the notable exception of the word mano ("hand") and a few words, which are reduced forms of longer words: foto ("photo") from fotografía, and moto ("motorcycle") from motocicleta; -a is typically feminine, with notable exceptions; other vowels and consonants are more often than not masculine, but many are feminine, particularly those referring to women (la madre) or ending in -ción/sión, -dad/tad, -ez (la nación, la televisión, la soledad, la libertad, la vejez).

A small set of words of Greek origin and ending in -ma, "-pa", or "-ta" are masculine: problema ("problem"), lema ("lemma, motto"), tema ("theme, topic"), sistema ("system"), telegrama ("telegram"), poeta ("poet"), planeta ("planet"), etc.

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