Voiceless bilabial nasal

The voiceless bilabial nasal (stop) is a type of consonantal sound, used in some spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is ⟨m̥⟩, a combination of the letter for the voiced bilabial nasal and a diacritic indicating voicelessness. The equivalent X-SAMPA symbol is m_0.

Features

Features of the voiceless bilabial nasal:

Its manner of articulation is occlusive, which means it is produced by obstructing airflow in the vocal tract. Because the consonant is also nasal, the blocked airflow is redirected through the nose.
Its place of articulation is bilabial, which means it is articulated with both lips.
Its phonation is voiceless, which means it is produced without vibrations of the vocal cords.
It is a nasal consonant, which means air is allowed to escape through the nose, either exclusively (nasal stops) or in addition to through the mouth.
Because the sound is not produced with airflow over the tongue, the central–lateral dichotomy does not apply.
Its airstream mechanism is pulmonic, which means it is articulated by pushing air solely with the intercostal muscles and abdominal muscles, as in most sounds.