A labial fricative is a fricative consonant, whose articulation involves the lips. Several kinds can be distinguished based on whether the articulation involves only the lips or either the teeth or the tongue: Bilabial fricatives (articulated with both lips): Voiceless bilabial fricative Voiced bilabial fricative Labiodental fricatives (articulated with the lower lip touching against the upper teeth): Voiceless labiodental fricative Voiced labiodental fricative Linguolabial fricatives (articulated with the tip or blade of the tongue against the upper lip: Voiceless linguolabial fricative or Voiced linguolabial fricative or