Latin (/ˈlætɨn/; Latin: lingua latīna; IPA: [ˈlɪŋɡʷa laˈtiːna]) is an ancient Italic language originally spoken by the Italic Latins in Latium and Ancient Rome. Along with most European languages, it is a descendant of the ancient Proto-Indo-European language. It originated in the Italian peninsula. Although it is considered a dead language, many modern languages (the Romance languages) are in fact living continuations of this language. Additionally, many students, scholars, and members of the Roman Catholic clergy speak it fluently, and it is still taught in primary and secondary and many post-secondary educational institutions around the world.
Latin is still used in the creation of new words in modern languages of many different families, including English, and in biological taxonomy. Latin and its daughter Romance languages are the only surviving languages of the Italic language family. Other languages of the Italic branch were attested in the inscriptions of early Italy, but were assimilated to Latin during the Roman Republic.
The extensive use of elements from vernacular speech by the earliest authors and inscriptions of the Roman Republic make it clear that the original, unwritten language of the Roman Monarchy was an only partially deducible colloquial form, the predecessor to Vulgar Latin. By the arrival of the late Roman Republic, a standard, literate form had arisen from the speech of the educated, now referred to as Classical Latin. Vulgar Latin, by contrast, is the name given to the more rapidly changing colloquial language, which was spoken throughout the empire.
Because of the Roman conquest, Latin spread to many Mediterranean regions, and the dialects spoken in these areas, mixed to various degrees with the autochthonous languages, developed into the modern Romance tongues. Classical Latin slowly changed with the Decline of the Roman Empire, as education and wealth became ever scarcer. The consequent Medieval Latin, influenced by various Germanic and proto-Romance languages until expurgated by Renaissance scholars, was used as the language of international communication, scholarship, and science until well into the 18th century, when it began to be supplanted by vernacular languages.
Latin is a highly inflected language, with three distinct genders, seven noun cases, four verb conjugations, six tenses, three persons, three moods, two voices, two aspects, and two numbers. A dual number ("a pair of") is present in Archaic Latin. One of the rarer of the seven cases is the locative, only marked in proper place names and a few common nouns. Otherwise, the locative function ("place where") has merged with the ablative. The vocative, a case of direct address, is marked by an ending only in words of the second declension. Otherwise, the vocative has merged with the nominative, except that the particle O typically precedes any vocative, marked or not. There are only five fully productive cases, that is, in the few instances of the formation of a distinct locative or vocative, the endings are specific to those words and cannot be placed on other stems of the declension to produce a locative or vocative. In contrast, the plural nominative ending of the first declension may be used to form any first declension plural.