1. One that deadens, restrains, or depresses: Rain put a damper on our picnic plans.
2. An adjustable plate, as in the flue of a furnace or stove, for controlling the draft.
a. A device in various keyboard instruments for deadening the vibrations of the strings.
b. A mute for various brass instruments.
4. A device that eliminates or diminishes vibrations or oscillations, as of a magnetic needle.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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