spirometer

An instrument for measuring the volume of air entering and leaving the lungs.

A contrivance for measuring the extreme differential capacity of the human lungs.

An instrument for measuring the vital capacity of the lungs, or the volume of air which can be expelled from the chest after the deepest possible inspiration. Cf. pneumatometer.

A device used to measure the volume of air inspired and expired by the lungs.

a measuring instrument for measuring the vital capacity of the lungs