Los

Los is a term with multiple uses in language, geography, and abbreviations. In Spanish, los is the masculine plural definite article, used before masculine or mixed-gender nouns, as in los libros. The feminine plural article is las. The sequence also appears as a direct object pronoun meaning “them”: Vi a los niños; los vi. When attached to an infinitive, the pronoun forms words like verlos.

In toponyms and common phrases, los occurs in many Spanish-language place names, often translating to “the” in phrases such as Los Ángeles (The Angels), Los Cabos (The Capes), and Los Baños (The Baths). In English-language usage, Los is sometimes retained in reference to these places as part of proper nouns.

LOS (uppercase) is a set of abbreviations used in various fields. Line of Sight is a key concept in telecommunications, navigation, and weapon aiming, describing the unobstructed path between observer and target. Length of Stay is used in healthcare, hospitality, and travel planning to denote how long a person remains in a facility or location. Other uses include Loss on Sale or Loss on Stock, depending on the industry. Because LOS can have multiple meanings, the intended sense is inferred from context.

As a word, “los” is distinct from “lo” (neuter article) and from “las” (feminine plural). It also appears in many proper names in the Spanish-speaking world and can function as both a definite article and a pronoun within sentences.