damper

(noun) a movable iron plate that regulates the draft in a stove or chimney or furnace.

(noun) a device that decreases the amplitude of electronic, mechanical, acoustical, or aerodynamic oscillations. Synonyms: muffler.

(noun) a depressing restraint. Example: "Rain put a damper on our picnic plans."

(adj) slightly wet. Synonyms: damp, dampish, moist. Examples: "Clothes damp with perspiration." "A moist breeze." "Eyes moist with tears."