Monophthongization

English

Some English sounds that may be perceived by native speakers as single vowels are in fact diphthongs; an example is the vowel sound in pay, pronounced . However, in some dialects (e.g. Scottish English) is a monophthong .

Some dialects of English make monophthongs from former diphthongs. For instance, Southern American English tends to realize the diphthong as in eye as a long monophthong , a feature known as /aj/ ungliding or /ay/ ungliding. Monophthongization is also one of the most widely used and distinguishing features of African American Vernacular English.

Smoothing

Smoothing is a monophthongization of a closing diphthong (most commonly ) before a vowel that can occur in Received Pronunciation and other accents of English. (Some have called this "levelling", but this is rarely used because it may be confused with dialect levelling.) For example, chaos, pronounced without smoothing, becomes with smoothing. Smoothing applies particularly readily to and when preceding , hence for fire and for tower, or with the syllabicity loss of , . The centring diphthong deriving from smoothing and syllabicity loss may further undergo monophthongization, realizing fire and tower as or , similar or identical to far, tar; unlike smoothing, this type of monophthongization (which Wells terms "monophthonging") does not require a following vowel.

Smoothing can occur across word boundaries in the same conditions (closing diphthong + vowel), as in way out, they eat, go off.

Old English

Indo-Aryan languages

Vedic Sanskrit diphthongs and later monophthongize to and respectively in Classical Sanskrit, but these may remain as diphthongs under sandhi rules.

In Hindustani, the pure vowels and are written with the letters for the diphthongs ai and au in Devanagari and related alphabets. The vowel sequences and exist in Hindi, but are written as āi and āu, with long initial vowels.

German

The so-called early frühneuhochdeutsche Monophthongierung (monophthongization in the earliest stages of New High German) is particularly important in today's Standard German. It changed the diphthongs ie , uo and üe to respectively ie , u and ü :

Before 11th century > nowadays:

• liebe > liebe
• guote > gute
• brüeder > Brüder

The digraph "ie" has kept its spelling despite monophthongization.

The New High German monophthongization started in the 11th century in the center of the German-speaking area. Bavarian and Alemannic dialects in the south did not undergo the monophthongization changes and thus these dialects remain in an older language state.

Greek

Greek underwent monophthongization at many points during its history. For instance, the diphthongs monophthongized to around the 5th century BC, and the diphthong monophthongized to in the Koine Greek period. For more information, see Ancient Greek phonology § Monophthongization and Koine Greek phonology.

French

French underwent monophthongization and so the digraph ⟨ai⟩, which formerly represented a diphthong, represents the sound or in Modern French. Similarly, the digraph ⟨au⟩ and trigraph ⟨eau⟩ represent the monophthong due to the same process.

Korean

Korean underwent monophthongization two times─18th century, and 20th century. Their common point is that all of the monophthongized vowels were falling diphthongs. In 18th century, monophthongized to . Similarly, in 20th century monophthongized to .