noun

1. the partition of muscles and tendons between the chest cavity and the abdominal cavity; midriff
2. 1. any membrane or partition that separates one thing from another
   2. a dividing wall at the node of a plant stem
3. a device to regulate the amount of light entering the lens of a camera, microscope, etc.
4. ☆ a small, flexible contraceptive device of rubber or plastic that fits over the cervix of the uterus
5. a thin, flexible disk or cone that vibrates in response to sound waves to produce electrical signals, as in a microphone, or that vibrates in response to electrical signals to produce sound waves, as in a speaker

Etymology: ME diafragma < LL diaphragma < Gr < dia-, through + phragma, a fence < phrassein, to enclose