diaphragm medical definition

1. A musculomembranous partition separating the abdominal and thoracic cavities and functioning in respiration. Also called midriff.
2. A membranous part that divides or separates.
3. A contraceptive device consisting of a thin flexible disk, usually made of rubber, that is designed to cover the uterine cervix to prevent the entry of sperm during sexual intercourse.
4. A disk having a fixed or variable opening used to restrict the amount of light traversing a lens or optical system.

Related Forms:

• diaphragmatic adjective

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diaphragm

Top: during inhalation the diaphragm contracts downward, forcing air into the lungs

Bottom: during exhalation the diaphragm relaxes upward, forcing air out of the lungs