[foh-toh-ak-tuh-vey-shuh n] /ˌfoʊ toʊˌæk təˈveɪ ʃən/
the activation or control of a chemical, chemical reaction, or organism by light, as the activation of chlorophyll by sunlight during photosynthesis.
(of a substance) capable of responding to light or other electromagnetic radiation
[foh-toh-ey-jing] /ˌfoʊ toʊˈeɪ dʒɪŋ/ noun 1. damage to the skin, as wrinkles or discoloration, caused by prolonged exposure to sunlight.
[foh-toh-uh-lur-jik] /ˌfoʊ toʊ əˈlɜr dʒɪk/ adjective 1. .
[foh-toh-an-l-ist] /ˌfoʊ toʊˈæn l ɪst/ noun 1. a person who analyzes and interprets photographs, especially a military specialist in aerial or satellite photography.
[foh-toh-aw-tuh-trof, -trohf] /ˌfoʊ toʊˈɔ təˌtrɒf, -ˌtroʊf/ noun, Biology. 1. any organism that derives its energy for food synthesis from light and is capable of using carbon dioxide as its principal source of carbon. photoautotroph (fō’tō-ô’tə-trŏf’, -trōf’) See phototroph.