the activation or control of a chemical, chemical reaction, or organism by light, as the activation of chlorophyll by sunlight during photosynthesis.
Origin of photoactivation
1920–25; photo- + activation
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
(of a substance) capable of responding to light or other electromagnetic radiation
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012