Diaphragm - Definition

n 1: a mechanical device in a camera that controls size of
aperture of the lens; "the new cameras adjust the diaphragm
automatically" [syn: diaphragm, stop]
2: (anatomy) a muscular partition separating the abdominal and
thoracic cavities; functions in respiration [syn:
diaphragm, midriff]
3: a contraceptive device consisting of a flexible dome-shaped
cup made of rubber or plastic; it is filled with spermicide
and fitted over the uterine cervix [syn: diaphragm,
pessary, contraceptive diaphragm]
4: electro-acoustic transducer that vibrates to receive or
produce sound waves