Voiceless labial–velar fricative
A voiceless labial–velar fricative, or more accurately a voiceless labialized velar fricative and sometimes analyzed as a voiceless labial–velar approximant, is a type of consonantal sound, used in spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is or, rather ambiguously,. The letter was defined as a "voiceless " until 1979, when it was defined as a fricative with the place of articulation of the same way that is an approximant with the place of articulation of. The IPA Handbook describes as a "fricative" in the introduction, while a chapter within characterizes it as an "approximant".
There was once some controversy over whether a voiceless approximant could be distinct from a fricative, but more recent research distinguishes between turbulent and laminar airflow in the vocal tract. English is an approximant, a labialized glottal fricative, or an sequence, not a velar fricative. Scots has been described as a velar fricative, especially in older Scots and peripheral dialects, where it is. Ladefoged and Maddieson were unable to confirm that any language has fricatives produced at two places of articulation, as the term "labial–velar" implies. They conclude that "if is a fricative, it is better described as a voiceless labialized velar fricative".