Dialect levelling in the context of "Codification (linguistics)"

Koine Greek (ἡ κοινὴ διάλεκτος, hē koinḕ diálektos, lit. 'the common dialect'), also variously known as Hellenistic Greek, common Attic, the Alexandrian dialect, Biblical Greek, Septuagint Greek or New Testament Greek, was the common supra-regional form of Greek spoken and written during the Hellenistic period, the Roman Empire, and the early Byzantine Empire. It evolved from the spread of Greek following the conquests of Alexander the Great in the fourth century BC, and served as the lingua franca of much of the Mediterranean region and the Middle East during the following centuries. It was based mainly on Attic and related Ionic speech forms, with various admixtures brought about through dialect levelling with other varieties.

Koine Greek included styles ranging from conservative literary forms to the spoken vernaculars of the time. As the dominant language of the Byzantine Empire, it developed further into Medieval Greek, which then turned into Modern Greek.

There is considerable dialectal variation in Turkish.

Turkish is a member of the Western Oghuz branch of the Turkic language family. Turkish is natively and historically spoken by the Turkish people in Turkey, Cyprus, Bulgaria, Greece (primarily in Western Thrace), Kosovo, Meskhetia, North Macedonia, Romania, Iraq, Syria and other areas of traditional settlement which formerly, in whole or part, belonged to the Ottoman Empire. Turkish is the official language of Turkey, the de facto country of North Cyprus and is one of the official languages of Cyprus. It also has official (but not primary) status in the Prizren District of Kosovo and several municipalities of North Macedonia, depending on the concentration of Turkish-speaking local population. Modern standard Turkish is based on the dialect of Istanbul. Nonetheless, dialectal variation persists, in spite of the levelling influence of the standard used in mass media and the Turkish education system since the 1930s. The terms ağız or şive are often used to refer to the different types of Turkish dialects (such as Cypriot Turkish).

Yorkshire dialect, also known as Yorkshire English, Broad Yorkshire, Tyke, or Yorkie, is a grouping of several regionally neighbouring dialects of English spoken in Yorkshire. Yorkshire experienced drastic dialect levelling in the 20th century, eroding many traditional features, though variation and even innovations persist, at both the regional and sub-regional levels. Organisations such as the Yorkshire Dialect Society and the East Riding Dialect Society exist to promote the survival of the more traditional features.

The dialects have been represented in classic works of literature such as Wuthering Heights, Nicholas Nickleby and The Secret Garden, and linguists have documented variations of the dialects since the 19th century. In the mid-20th century, the Survey of English Dialects collected dozens of recordings of authentic Yorkshire dialects.

Peninsular Spanish (Spanish: español peninsular), also known as the Spanish of Spain (Spanish: español de España), European Spanish (Spanish: español europeo), or Iberian Spanish (Spanish: español ibérico), is the set of varieties of the Spanish language spoken in Peninsular Spain. This construct is often framed in opposition to varieties from the Americas and the Canary Islands.

From a phonological standpoint, there is a north-south gradient contrasting conservative and innovative pronunciation patterns. The former generally retain features such as /s/ – /θ/ distinction and realization of intervocalic /d/, whilst the latter may not. Processes of interaction and levelling between standard (a construct popularly perceived as based on northern dialects) and nonstandard varieties however involve ongoing adoption of conservative traits south and innovative ones north. In line with Spanish language's rich consonant fluctuation, other internal variation within varieties of Peninsular Spanish is represented by phenomena such as weakening of coda position -/s/, the defricativization of /tʃ/, realizations of /x/ as [x] and [h] and weakening or change of liquid consonants /l/ and /r/.