in music, a small felted block which prevents or stops the vibration of a piano string
a device, e.g. a shock absorber, designed to reduce vibration or bring a mechanism to rest with minimum oscillation
a valve or plate in the flue of a furnace for regulating the draught
chiefly Aus, NZ a loaf or scone of unleavened bread made with flour and water and baked in the ashes of a fire
put a damper on
to have a dulling or restraining influence on (somebody or something)