Carinthia (German: Kärnten [ˈkɛʁntn̩] ^ⓘ; Slovene: Koroška [kɔˈɾóːʃka] ^ⓘ or avstrijska Koroška; Italian: Carinzia [kaˈrintsja]) is the southernmost and least densely populated Austrian state, in the Eastern Alps, and is noted for its mountains and lakes. The Lake Wolayer is a mountain lake on the Carinthian side of the Carnic Main Ridge, near the Plöcken Pass. The main language is Austrian German, with its non-standard dialects belonging to the Southern Bavarian group; Carinthian Slovene dialects, forms of a South Slavic language that predominated in the southeastern part of the region up to the first half of the 20th century, are now spoken by a small minority in the area.

Carinthia's main industries are tourism, electronics, engineering, forestry, and agriculture.

The etymology of the name "Carinthia", similar to Carnia or Carniola, has not been conclusively established. The Ravenna Cosmography (about AD 700) referred to a Slavic "Carantani" tribe as the eastern neighbours of the Bavarians. In his History of the Lombards, the 8th-century chronicler Paul the Deacon mentions "Slavs in Carnuntum, which is erroneously called Carantanum" (Carnuntum, quod corrupte vocitant Carantanum) for the year 663.

"Carantani" may have been formed from a toponymic base carant- which ultimately derives from pre-Indo-European root *karra 'rock'. (cf. Friulian: carantàn), or that it is of Celtic origin and derived from *karantos 'friend, ally'.

Likewise, the Slovene name *korǫtanъ may have been adopted from the Latin *carantanum. The toponym Carinthia (Slovene: Koroška < Proto-Slavic *korǫt’ьsko) is also claimed to be etymologically related, deriving from pre-Slavic *carantia.

Carinthia is known as Koruška/ Корушка in Croatian and Serbian, Korutany in Czech, Kärnten in German, Karintia in Hungarian, Carinzia in Italian, Carintia in Spanish, Karyntia in Polish, Korutánsko in Slovak, and Koroška in Slovene.

The state stretches about 180 km (110 mi) from east to west, and 70 km (43 mi) in a north–south direction. With 9,536 km² (3,682 sq mi), it is the fifth-largest Austrian state by area. Most of the larger Carinthian towns and lakes are situated within the Klagenfurt Basin in the southeast, an inner Alpine sedimentary basin covering about one-fifth of the area. These Lower Carinthian lands differ from the mountainous Upper Carinthian region in the northwest, stretching up to the Alpine crest.

The Carinthian lands are confined by mountain ranges: the Carnic Alps and the Karawanks form the border to Italy (Friuli-Venezia Giulia) and Slovenia (Carinthia Statistical Region, Savinja Statistical Region and Upper Carniola Statistical Region). The High Tauern mountain range with Mt Grossglockner, 3,797 m (12,457 ft), separates it from the state of Salzburg in the northwest. To the northeast and east beyond the Pack Saddle mountain pass is the state of Styria. The main river of Carinthia is the Drava (Drau), it makes up a continuous valley with East Tyrol, Tyrol to the west. Tributaries are the Gurk, the Glan, the Lavant, and the Gail rivers. Carinthia's lakes including Wörther See, Millstätter See, Lake Ossiach, and Lake Faak are a major tourist attraction.