1. The taking in, incorporation, or reception of gases, liquids, light, or heat. Cf. adsorption.
2. In radiology, the uptake of energy from radiation by the tissue or medium through which it passes. See: half-value layer.
3. In radiation or medical physics, the number of disintegrations per second of a radionuclide. Radioactivity. Unit (SI): becquerel.
[L. absorptio, fr. absorbeo, to swallow]
electron resonance absorption