The voiceless bilabial fricative is a type of consonantal sound, used in some spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is ɸ, and the equivalent X-SAMPA symbol is p\.

IPA - Unicode	ɸ
IPA - image
X-SAMPA	p\
Kirshenbaum	P
Sound sample

Features of this consonant:

• Its manner of articulation is fricative, which means it is produced by constricting air flow through a narrow channel at the place of articulation, causing turbulence.
• Its place of articulation is bilabial which means it is articulated with both lips,
• Its phonation type is voiceless, which means it is produced without vibrations of the vocal cords.
• It is an oral consonant, which means air is allowed to escape through the mouth.
• It is a central consonant, which means it is produced by allowing the airstream to flow over the center of the tongue, rather than the sides.
• The airstream mechanism is pulmonic egressive, which means it is articulated by pushing air out of the lungs and through the vocal tract, rather than from the glottis or the mouth.

Occurs as:

• Greek phoneme /φ/
• Spanish phoneme /f/
• Japanese phoneme /f/