noun (n)

• a mechanical device in a camera that controls size of aperture of the lens(noun.artifact)

  Example:
  The new cameras adjust the diaphragm automatically.
  

  Synonym:
  stop
  

  source: wordnet30
• (anatomy) a muscular partition separating the abdominal and thoracic cavities; functions in respiration(noun.body)

  Synonym:
  midriff
  

  source: wordnet30
• 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.artifact)

  Synonym:
  contraceptive diaphragm, pessary
  

  source: wordnet30
• electro-acoustic transducer that vibrates to receive or produce sound waves(noun.artifact)

  source: wordnet30
• A dividing membrane or thin partition, commonly with an opening through it.(noun)

  source: webster1913