otro

Otro is a Spanish word that functions as an adjective and a pronoun meaning "other" or "another." It agrees in gender and number with the noun it modifies: otro (masc. singular), otra (fem. singular), otros (masc. plural), otras (fem. plural). It derives from Latin alter, altera, alterum, and entered Old Spanish through the Romance language continuum.

As a determiner, otro precedes a noun: otro día, otra historia, otros libros. It can also be used with the noun omitted when the meaning is understood from context, as in ¿Quieres otro? meaning “Do you want another one?” As a pronoun, it can stand for a previously mentioned noun and is inflected in gender and number as el otro, la otra (the other one); los otros, las otras (the others).

Common expressions and idioms include de otro modo (in another/another way), de otro tipo (of another kind), and otro gallo cantaría (the situation would be different). The phrase otro día is used to refer to a future point or the following day, while otro tanto means the same amount again.

Etymology and related forms: from Latin alter, via Old Spanish to modern Spanish. Cognates appear in other Romance languages, such as portuguese outro, italian altro, and french autre, reflecting a shared origin.

Usage notes: in Spanish, otro usually appears without an article when modifying a noun, e.g., otro libro. When referring to the distinct counterpart, masculine or feminine articles with el/la are used (el otro, la otra). The word is common across dialects and registers, with frequent appearances in everyday speech and literature.