[kuh
m-pres-er] 
| 1. | a person or thing that compresses. |
| 2. | Anatomy. a muscle that compresses some part of the body. |
| 3. | Surgery. an instrument for compressing a part of the body. |
| 4. | a pump or other machine for reducing volume and increasing pressure of gases in order to condense the gases, drive pneumatically powered machinery, etc. |
| 5. | Electronics. a transducer that produces an output with a range of voltages whose ratio is smaller than that of the range of the input signal. Compare expander (def. 2). |
| com·pres·sor (kəm-prěs'ər) n. One that compresses, especially: a. Mechanics A pump or other machine that increases the pressure of a gas. |
compressor com·pres·sor (kəm-prěs'ər)
n.
A muscle that causes compression of a structure upon contraction.