lucid

Clearly expressed; easily understood.

Thinking or expressing oneself clearly, especially between periods of confusion; clearheaded.

Brightly lit; luminous.

Clear; transparent.

Emitting light; shining; bright; resplendent: as, the lucid orbs of heaven.

Transmitting or reflecting light; clear; transparent; pellucid: as, a lucid stream.

Marked by intellectual clearness or brightness; free from obscurity or confusion of thought, or, specifically, from delirium; clear headed; sane: as, a lucid mind; lucid perceptions; lucid intervals in insanity.

Presenting a clear view; easily understood; distinct: as, a lucid order or arrangement; a lucid style of writing.

In entomology

Smooth and very shining; reflecting light like polished metal.