CFM is cubic feet per minute. The amount of air, in cubic feet, that Flows through a given space in one minute. 1 CFM equals approximately 2 liters per second (l/s).

---

Other /More definition:
Cubic feet per minute. The amount of air, in cubic feet, that flows through a given space in one minute. 1 CFM equals approximately 2 liters per second (l/s).