compression /kəmpresh″ən/ [L, comprimere, to press together] , 1. the act of pressing, squeezing, or otherwise applying pressure to an organ, tissue, or body area. An intracranial tumor or hemorrhage may cause compression of brain tissue. Kinds of pathological compression include compression fracture, in which bone surfaces are forced against each other, causing a break, and compression paralysis, marked by paralysis of a body area caused by pressure on a nerve. 2. the pressing or squeezing of substances together so that they occupy a smaller volume of space (e.g., compressing gas into a pressurized aerosol can).
