A noun it's a class of words that can work as subject of a sentence and that designates or identifies an animate or inanimate being .
In Romance languages, such as Spanish, nouns vary according to gender and the number . In other languages, such as Chinese, nouns never vary. There are languages where there are not even different formal properties between nouns and verbs, such as Nahuatl.
From a point of view semantic:
* concrete nouns: they refer to independent concepts, which we can perceive with our senses, or imagine and assume that they exist on our same plane (a chair, a computer, a person);
* abstract nouns: contrary to the previous case, these are dependent concepts, which serve to designate entities imperceptible by our sensory abilities, but perceptible through thought (friendship, love, evil, faith).
In turn, abstract nouns can be classified into:
+ quality abstracts: are related to adjectives and represent properties or qualities of animate or inanimate beings (ugliness, height);
+ phenomenon abstracts: that serve to designate states, actions or their consequences (exercise, study);
+ abstract numbers: allow quantifying other nouns, with varying degrees of precision (branch, group, quantity).
According to the quality of unique:
* common nouns: considered generic nouns, they are used to refer to any member of the same species or class without entering their characteristics individuals (woman, dog, car);
* nouns: serve to distinguish each individual from others, as with the names of cities or people, and must be written in their initial capital letter (Tokyo, Cecilia).
Taking into account the type of reference:
* individual nouns: when they present their singular form they refer to a single copy of a class or species (leaf, stream, mountain). In languages whose grammar contemplates the plural form, as is the case with Spanish, these nouns can designate a group (undefined unless numerical information is added);
* collective nouns: they are used to name a group of objects or beings, even in their singular form (city, grove, herd, equipment). In their plural form, they give the idea of sets of the same class independent of each other.
From its composition:
* simple nouns: these are words formed by a single term (vessel, control, housing);
* Compound nouns: are formed from the union of two simple words (windshield, dropper, goalkeeper, firewall).
According to the complexity of its morphology or its origin:
* primitive nouns: they are those that have the main role in a family of words, that represent their root, and are formed from a basic lexeme (minimum unit, without grammatical morphemes) and may or may not adopt morphemes for their gender and number (flower, sea);
* derived nouns: are generated based on the primitive terms, thanks to the use of prefixes or suffixes (florist, marine);
* augmentative nouns: they are used to refer to animate or inanimate beings of considerable dimensions or of great intensity (cochazo, notion, blow, espadota);
* diminutive nouns: the opposite case of augmentatives (puppy, dog, house, package);
* derogatory nouns: as the name implies, they serve to mention with contempt beings or objects, trying to subtract them value or importance (cuartucho, casucha, gentuza, poblacho);
* gentile nouns: they exist from the name of a country, a city or any officially recognized territory, and are used to refer to the place of origin of a person, an animal or a thing (Japanese, North American, Italian).
Taking into account your accounting:
* countable nouns: are concepts that can be counted (stone, cup, currency);
* uncountable nouns: designate concepts that cannot be divided into accounting portions (Water, happiness, oxygen, gas, oil).