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diaphragm

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noun di·a·phragm \ˈdī-ə-ˌfram\

Simple Definition of diaphragm

  • medical : a large flat muscle that separates the lungs from the stomach area and that is used in breathing

  • : a device that controls the amount of light passing through the lens of a camera

  • : a device shaped like a cup that is placed in the vagina to prevent pregnancy

Full Definition of diaphragm

  1. 1 :  a body partition of muscle and connective tissue; specifically :  the partition separating the chest and abdominal cavities in mammals

  2. 2 :  a dividing membrane or thin partition especially in a tube

  3. 3 a :  a more or less rigid partition in the body or shell of an invertebrate b :  a transverse septum in a plant stem

  4. 4 :  a device that limits the aperture of a lens or optical system — compare iris diaphragm

  5. 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. 6 :  a molded cap usually of thin rubber fitted over the uterine cervix to act as a mechanical contraceptive barrier

di·a·phrag·mat·ic play \ˌdī-ə-frə(g)-ˈma-tik, -ˌfrag-\ adjective
di·a·phrag·mat·i·cal·ly play \-ˈma-ti-k(ə-)lē\ adverb

Origin of diaphragm

Middle English diafragma, from Late Latin diaphragma, from Greek, from diaphrassein to barricade, from dia- + phrassein to enclose


First Known Use: 14th century


Medical Dictionary

diaphragm

play
noun di·a·phragm \ˈdī-ə-ˌfram\

Medical Definition of diaphragm

  1. 1:  a body partition of muscle and connective tissue; specifically :  the partition separating the chest and abdominal cavities in mammals—see pelvic diaphragm, urogenital diaphragm

  2. 2:  a device that limits the aperture of a lens or optical system

  3. 3:  a molded cap usually of thin rubber fitted over the uterine cervix to act as a mechanical contraceptive barrier



Illustration of diaphragm



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