The definition of luminescent is something or someone that glows or emits light.(adjective)
A lamp that emits bright light is an example of something that would be described as luminescent.
See luminescent in Webster's New World College Dictionary
Origin: < L lumen, light + -escent
See luminescent in American Heritage Dictionary 4
Origin: Latin lūmen, lūmin-, light; see lumen
Origin: + -escent.
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