In phonetics and phonology, a bilabial stop is a type of consonantal sound, made with both lips (hence bilabial), held tightly enough to block the passage of air (hence a stop consonant). The most common sounds are the stops [p] and [b], as in English pit and bit, and the voiced nasal [m]. More generally, several kinds are distinguished:

• [p], voiceless bilabial plosive
• [b], voiced bilabial plosive
• [m], voiced bilabial nasal
• [m̥], voiceless bilabial nasal
• [ɓ], voiced bilabial implosive
• [pʼ], bilabial ejective (rare)
• [ɓ̥] or [pʼ↓], voiceless bilabial implosive (very rare)