|a calculus or concretion found in the stomach or intestines of certain animals, esp. ruminants, formerly reputed to be an effective remedy for poison.|
|an arrangement of five objects, as trees, in a square or rectangle, one at each corner and one in the middle.|
|1.||readily understood; clear|
|2.||shining or glowing|
|3.||psychiatry of or relating to a period of normality between periods of insane or irresponsible behaviour|
|[C16: from Latin lūcidus full of light, from lūx light]|
lucidity lu·cid·i·ty (l&oomacr;-sĭd'ĭ-tē)
Clarity, especially mental clarity.