 Labiodental consonant

A labiodental consonant forms its principal constriction between the lower lip and upper teeth. This is a place of articulation, distinct from the two-lip constriction of a bilabial consonant. It does not by itself specify voicing or manner of articulation.^[ref]

The familiar sounds [f] and [v] are labiodental fricatives. Comparing them keeps the constriction location similar while changing the usual voicing category. Comparing [f] with [p] instead changes both the contact surface and the airflow mechanism. A mirror can show lower-lip contact with the upper teeth, while acoustic phonetics examines the resulting noise and periodicity.