lucid

[loo-sid]

adjective

1. easily understood; completely intelligible or comprehensible.

   a lucid explanation.

   Synonyms: obvious, evident, understandable, plain
   Antonyms: obscure

2. characterized by clear perception or understanding; rational or sane.

   a lucid moment in his madness.

   Synonyms: reasonable, sound
   Antonyms: irrational

3. shining or bright.

   Synonyms: luminous, radiant
   Antonyms: dim

4. clear; pellucid; transparent.

   Synonyms: limpid
   Antonyms: obscure

lucid

/ ˈluːsɪd /

adjective

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

Other Word Forms

• lucidity noun
• lucidness noun
• lucidly adverb
• nonlucid adjective
• nonlucidly adverb
• nonlucidness noun
• unlucid adjective
• unlucidly adverb
• unlucidness noun

Word History and Origins

Origin of lucid¹

First recorded in 1575–85; from Latin lūcidus, equivalent to lūc- (stem of lūx light ¹ ) + -idus -id ⁴

Word History and Origins

Origin of lucid¹

C16: from Latin lūcidus full of light, from lūx light

Example Sentences

Might a patient with an empty skull become lucid?

Read more on The Wall Street Journal

The legislation gives lucid, terminally ill patients the right to aid in dying if their suffering is unbearable and all treatment options have been exhausted.

Read more on Barron's

She starts lucid dreaming and sleepwalking, receiving phone calls from beyond — like from their dead mother when she was a teenager beyond.

Read more on Los Angeles Times

The hearing was also told that Mrs Kneale's family said she was "chatty", lucid and did not appear agitated when they left her at the hospital late on the evening of 12 November.

Read more on BBC

And while he does so, he remains always calm and lucid.

Read more on BBC

Related Words

• rational 
• sane 
• sober