Definition of diaphragm in English:


Line breaks: dia|phragm
Pronunciation: /ˈdʌɪəfram


  • 1A dome-shaped muscular partition separating the thorax from the abdomen in mammals. It plays a major role in breathing, as its contraction increases the volume of the thorax and so inflates the lungs.
    More example sentences
    • Contraction of the expiratory muscles displaces the abdomen inward and the diaphragm upward into the thorax during exhalation.
    • Metastatic tumor was also found in the thyroid gland, pericardium, myocardium, bilateral lungs, diaphragm, bilateral kidneys, and liver.
    • Separating the chest from the abdomen, the diaphragm (pronounced: die-uh-fram) plays a lead role in breathing.
  • 2A thin sheet of material forming a partition.
    More example sentences
    • In this way the stalk expands radially to form a hemifusion diaphragm.
    • The trans layers make contact and produce an axially symmetric hemifusion diaphragm.
    • New growth cycles began with the formation of new basal diaphragms and lateral walls of living chambers.
  • 2.1A taut flexible membrane in mechanical or acoustic systems.
    More example sentences
    • The flexible metal diaphragm provides expansion capability to partially compensate for thermal expansion mismatch between the liquids and the cylinder.
    • The diaphragm is a flexible disk made of sheet metal with ridges carved into it.
    • A diaphragm extends around the shaft and defines fluidly separate upper and lower chambers within a valve body.
  • 3A thin contraceptive cap fitting over the cervix.
    More example sentences
    • Find out from this factsheet by the fpa how contraceptive diaphragms and caps work, how effective they are at preventing pregnancy and their advantages and disadvantages.
    • Barrier methods of contraception include diaphragms, condoms and cervical caps.
    • Following his logic, we would have to say that Catholics who insist on using contraceptives should opt for condoms or diaphragms.
  • 4A device for varying the effective aperture of the lens in a camera or other optical system.
    More example sentences
    • If you know how the combination of a shutter, a lens, a diaphragm, and a light meter can make a picture.
    • From the images above you can clearly see the lenses are identical even down to the aperture diaphragm, which begs the question is the lens in the PhotoPC 3000Z a Carl Zeiss design?
    • It is not much unlike a conventional camera in the conception of design, consisting of a lens and a diaphragm that adjust the focus and control the amount of light coming through.



Pronunciation: /ˌdʌɪəfragˈmatɪk/
More example sentences
  • They also found he was suffering from a diaphragmatic hernia.
  • The relationship between diaphragmatic surface area and a given lung volume may be different during active breathing.
  • Prolonged mechanical ventilation results in diaphragmatic atrophy and contractile dysfunction, but its effect on the rate of protein synthesis is not known.


late Middle English: from late Latin diaphragma, from Greek, from dia 'through, apart' + phragma 'a fence'.

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