Definition of diaphragm
1
: a body partition of muscle and connective tissue
specifically
: the partition separating the chest and abdominal cavities in mammals
2
: a dividing membrane or thin partition especially in a tube
3a
: a more or less rigid partition in the body or shell of an invertebrate
b
: a transverse septum in a plant stem
4
: a device that limits the aperture of a lens or optical system — compare iris diaphragm
5
: a thin flexible disk (as in a microphone or loudspeaker) that vibrates when struck by sound waves or that vibrates to generate sound waves
6
: a molded cap usually of thin rubber fitted over the uterine cervix to act as a mechanical contraceptive barrier
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Merriam-Webster unabridged
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Time Traveler for diaphragm
The first known use of diaphragm was in the 14th century
See more words from the same century