Basic Meaning
In a general sense, that which clears away darkness, though it often appears in Buddhist literature in reference to the mind or its nature. It is a particularly salient feature of Tantric literature, especially in regard to the advanced meditation techniques of the completion-stage yogas.
Has the sense of
Radiance, brilliance, or effulgence.
See page 653: In Sanskrit, “luminous,” “resplendent”; referring to an effulgence of light and often used as a metaphor for either deep states of meditation or, especially, the nature of the mind.
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