1. A mechanical device in a camera that controls size of aperture of the lens Noun
2. (anatomy) a muscular partition separating the abdominal and thoracic cavities; functions in respiration Noun
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 Noun
4. Electro-acoustic transducer that vibrates to receive or produce sound waves Noun