Voiceless labial–velar fricative

The voiceless labial–velar fricative is a type of consonantal sound, used in spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is ⟨xʷ⟩ or occasionally ⟨ʍ⟩. The letter ⟨ʍ⟩ was defined as a "voiceless [w]" until 1979, when it was defined as a fricative with the place of articulation of [k͡p] the same way that [w] is an approximant with the place of articulation of [ɡ͡b]. The IPA Handbook describes ⟨ʍ⟩ as a "fricative" in the introduction (IPA 1999: ix) while a chapter within characterizes it as an "approximant" (IPA 1999: 136).

Some linguists posit voiceless approximants distinct from voiceless fricatives. To them, English /ʍ/ is an approximant [w̥], a labialized glottal fricative [hʷ], or an [hw] sequence, not a velar fricative. Scots /ʍ/ has been described as a velar fricative, especially in older Scots, where it was [xw]. Other linguists believe that a "voiceless approximant" is a contradiction in terms, and so [w̥] must be the same as [xʷ]. Ladefoged and Maddieson were unable to confirm that any language has fricatives produced at two places of articulation, like labial and velar. They conclude that "if it is a fricative, it is better described as a voiceless labialized velar fricative".