Slovene or Slovenian (slovenski jezik or slovenščina, not to be confused with Slovak or slovenčina) is a South Slavic language spoken by approximately 2.4 million speakers worldwide, the majority of whom live in Slovenia. Slovene is one of the 23 official and working languages of the European Union.

Standard Slovene is the national language that evolved from the Central Slovene dialects in the 18th century and consolidated itself through the 19th and 20th centuries. While distinct regional varieties descended from the older rural dialects still exist, the spoken and written language is uniform and standardized. Some dialects differ considerably from the standard language in grammar and vocabulary. Though not facing imminent extinction, such dialects have been in decline during the past century, despite the fact that they are well researched and their use is not discouraged by the authorities. Notable exceptions are the Prekmurje dialect, which is one of the few Slovene dialects in Slovenia still widely used by all strata of the local population, and some Slovene dialects in Italy, most notably the Resian dialect.

Alongside Croatian and Serbian, Slovene is an Indo-European language belonging to the Western subgroup of the South Slavic branch of the Slavic languages. It is close to the Kajkavian and Čakavian dialects of Croatian, but is further from the Štokavian dialect, the basis for the Bosnian, Croatian and Serbian standard language.