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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

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

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

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

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

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

A dividing membrane or thin partition, commonly with an opening through it.

The muscular and tendinous partition separating the cavity of the chest from that of the abdomen; the midriff.

A calcareous plate which divides the cavity of certain shells into two parts.

A plate with an opening, which is generally circular, used in instruments to cut off marginal portions of a beam of light, as at the focus of a telescope.

A partition in any compartment, for various purposes.

A dividing membrane or thin partition, commonly with an opening through it.

The muscular and tendinous partition separating the cavity of the chest from that of the abdomen; the midriff.

A calcareous plate which divides the cavity of certain shells into two parts.

A plate with an opening, which is generally circular, used in instruments to cut off marginal portions of a beam of light, as at the focus of a telescope.

A partition in any compartment, for various purposes.

The musculofibrous partition that separates the thoracic cavity from the abdominal cavity. Contraction of the diaphragm increases the volume of the thoracic cavity aiding inspiration.

Muscles separating thoracic and abdominal cavities.

A thin partition or dividing membrane: the muscle which separates the chest from the abdomen; called also the midriff.

Partition; muscular partition separating the chest from the abdomen.

The wall which separates the small cell, the prothallus, from the rest of the macrospore in Hydropterideae; a septum at the nodes in Equisetum; a sheet of muscular tissue attached to the introvert in worms; the single strongly developed septum in the Terebelliformia; the perforated tissue that subdivides the tentacle cavity in Polyzoa; the transverse septum separating the cephalothorax from the abdomen in certain Arachnids; a special fan-shaped muscle spreading from the anterior end of the ilia to the oesophagus and base of the lungs in Anura; a partition partly muscular, partly tendinous, separating the cavity of the chest from the abdominal cavity.

Diaphragma, Diaphraxis, Respiratorium Ventris, Discretorium, Phrenes, Septum transversum, Discrimen Thoracis et Ventris, Disceptum, Cinetus, Diazoma, Proecinctus, Diazosma, Diazostra, Hypezocus, Hypozoma, Perizoma, Disseptum, Dissipium, Proecordia, Succingens membrana seu musculus, Succinctus, Succinctura, the Midriff, (Prov.) Heartscirts, from Sia, 'between,' and 'I close.' A large, azygous muscle; stretched transversely between the thoracic and abdominal cavities, which it separates from each other; tendinous in the centre; thin, almost circular, and unequally convex, upwards. It is fleshy at its circumference, which is attached to the cartilago ensiformis, to the last six ribs, to the aponeurosis stretched from the last rib to the transverse process of the first lumbar vertebra; and, lastly, to the bodies of the first three or four lumbar vertebriae, When it contracts, its fibres become straight, the chest is enlarged, and the abdomen diminished. It is then an inspiratory muscle. It may, also, diminish the capacity of the chest, and be an expiratory muscle. The muscle plays an important part in sighing, yawning, coughing, sneezing, laughing, sobbing, crying, hiccoughing, singing, vomiting, and excretion of the faeces and urine, the expulsion of the foetus, &c.

The midriff, or septum between the thorax and abdomen.

Any thin septum which divides a cavity.

In general, a partition or septum which more or less completely separates one cavity from another. Specifically, the musculotendinous partition separating the thoracic and abdominal cavities. In microscopy, a disk with an opening which admits light to the lenses of a microscope.

n. [Greek] A dividing membrane or thin partition;—the muscle separating the chest or thorax from the abdomen; the midriff.

The midriff which divides the upper cavity of the body from the lower; any division or partition which divides a hollow body.