a. Emitting light, especially in the dark; shining.
b. Reflecting light; illuminated: "He watched a luminous cloud drifting up from the Gulf" (Tim Gautreaux). See Synonyms at bright.
2. Having a high degree of saturation: a luminous green.
a. Presented or perceived clearly or vividly: luminous memories.
b. Enlightened or intelligent: luminous ideas.
[Middle English, from Old French lumineux, from Latin lūminōsus, from lūmen, lūmin-, light; see leuk- in the Appendix of Indo-European roots.]
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