Meaning
The quantum of light and other electromagnetic energy, regarded as a discrete particle having zero rest mass, no electric charge, and an indefinitely long lifetime. It is a gauge boson.
Etymology
Origin: Unknown
From photo- + -on. Coined by American physicist Leonard Troland in 1916 as a unit of light hitting the retina, and later popularized in a more modern sense by Gilbert N. Lewis, with the term gaining acceptance in the physics community by the late 1920s.
Synonyms & Antonyms
NYT Puzzle Appearances
Accepted in 2 recorded puzzles: