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lucid

/ˈluːsɪd/

clear, bright, and easy to understand

From Latin luc- (light).

adjective
noun
luc-
Proto-Indo-European
Verified
*leuk-
reconstructed
to shine, be bright

from PIE root *leuk- "to shine, be bright." Sense of "easy to understand, free

Latin
AI-inferred
lux, lucis
light
Latin
AI-inferred
lucere
to shine
Latin
Verified
lucidus
bright, clear, luminous

from Latin lucidus "light, bright, clear," figuratively "perspicuous, lucid, clear,"

Modern English
Verified
lucid
shifted from physical brightness to mental clarity

from Latin lucidus "light, bright, clear," figuratively "perspicuous, lucid, clear,"

Modern English
AI-inferred
lucid interval
a temporary period of clarity, especially in illness
Modern English
lucid

A word that once meant simply “bright” has a neat habit of drifting indoors and lighting up the mind. Romans used lucidus for things that gleamed, but English later stole it for thoughts, arguments, and prose that are wonderfully easy to see through. That same little light-root gives us luminous cousins like elucidate, pellucid, and lucent, all acting as if clarity were a kind of lamp. Then there’s the eerie phrase lucid interval, borrowed from Medieval Latin legal and medical writing: a person in distress or madness could still have brief spells of calm, as if the storm clouds opened for a minute. By the 1590s, English had the shine; by 1786, it had the mental clarity. One root, two kinds of light — the kind on a candle and the kind in your head.

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