lucid /ˈl(j)uːsɪd/adjective 3noun 1forms 5 adjective3 •Clear; easily understood.[T]he book, constructed in short, lucid episodes, can be satisfyingly read as a sequence of provocative talks, at once well informed and vatic. — 2014 •Mentally rational; sane. •Bright, luminous, translucent, or transparent.The atmosphere was unusually clear, as if loath to part with the daylight; but the moon, like a round of lucid snow, had risen on the sky; and a pale, soft gleam, came from the lamps amid the foliage. — 1837 noun1 •A lucid dream.The day before nightmare-initiated lucids, subjects reported more depressed feelings[…] — 1986 formslucids · lucider · more lucid · lucidest · most lucid