Common gender divisions include masculine and feminine; masculine, feminine and neuter; or animate and inanimate. In a few languages, the gender assignment of nouns is solely determined by their meaning or attributes, like biological sex, humanness, animacy. However, in most languages, this semantic division is only partially valid, and many nouns may belong to a gender category that contrasts with their meaning (e.g. the word for "manliness" could be of feminine gender). In this case, the gender assignment can also be influenced by the morphology or phonology of the noun, or in some cases can be apparently arbitrary.
Grammatical gender manifests itself when words related to a noun like determiners, pronouns or adjectives change their form (inflect) according to the gender of noun they refer to (agreement). The parts of speech affected by gender agreement, the circumstances in which it occurs, and the way words are marked for gender vary between languages. Gender inflection may interact with other grammatical categories like number or case. In some languages the declension pattern followed by the noun itself will be different for different genders.
Grammatical gender is found in many Indo-European languages (including Spanish, French, Portuguese, Russian, and German—but not Persian, for example), Afroasiatic languages (which includes the Semitic and Berber languages, etc.), and in other language families such as Dravidian and Northeast Caucasian, as well as several Australian Aboriginal languages such as Dyirbal, and Kalaw Lagaw Ya. Most Niger–Congo languages also have extensive systems of noun classes, which can be grouped into several grammatical genders. Conversely, grammatical gender is usually absent from the Koreanic, Japonic, Tungusic, Turkic, Mongolic, Austronesian, Sino-Tibetan, Uralic and most Native American language families. Modern English makes use of gender in pronouns, which are generally marked for natural gender, but lacks a system of gender concord within the noun phrase which is one of the central elements of grammatical gender in most other Indo-European languages.
In languages with grammatical gender, each noun is assigned to one of the classes called genders, which form a closed set. Most such languages usually have from two to four different genders, but some are attested with up to 20.
The division into genders usually correlates to some degree, at least for a certain set of nouns (such as those denoting humans), with some property or properties of the things that particular nouns denote. Such properties include animacy or inanimacy, "humanness" or non-humanness, and biological sex.
Few or no nouns can occur in more than one class. Depending on the language and the word, this assignment might bear some relationship with the meaning of the noun (e.g. "woman" is usually feminine), or may be arbitrary.
Gender is considered an inherent quality of nouns, and it affects the forms of other related words, a process called agreement. Nouns may be considered the "triggers" of the process, whereas other words will be the "target" of these changes.