1. a substance or material that reduces, absorbs, or suppresses sound, vibration, light, or other sensory effects
Usage: commonly used in construction, automotive, and audio engineering contexts
2. something that reduces intensity, enthusiasm, or liveliness
Usage: figurative use

Examples

• The car manufacturer installed acoustic deadener in the doors to reduce road noise.
• Foam deadener panels are commonly used in recording studios to improve sound quality.
• The bad weather was a deadener for the outdoor concert plans.
• Rubber deadener material helps minimize vibrations in machinery.
• His constant complaints acted as a deadener on the team's morale.
• The insulation includes a deadener layer to block heat transfer.