1. the ability of a material to absorb electromagnetic radiation, especially light or heat
Usage: physics; technical

Examples

• The black paint has high absorptivity for solar radiation.
• Scientists measured the absorptivity of different materials under infrared light.
• The absorptivity of the surface affects how much heat it retains.
• Materials with low absorptivity reflect most of the incident energy.
• The absorptivity coefficient varies with wavelength.
• Engineers consider absorptivity when designing solar panels.