1. (

• diaphragm ,
• stop ,

) a mechanical device in a camera that controls size of aperture of the lens; "the new cameras adjust the diaphragm automatically" ;

2. (

• diaphragm ,
• midriff

) (anatomy) a muscular partition separating the abdominal and thoracic cavities; functions in respiration ;

3. (

• diaphragm ,
• pessary ,
• contraceptive_diaphragm

) 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 ;

4. (

• diaphragm ,

) electro-acoustic transducer that vibrates to receive or produce sound waves ;