Meanings
- A form of illogical argument asserting that two things are related because they have opposite significations.
This Sun, into which Jones was now conducted, was truly named, as lucus a non lucendo; for it was an apartment into which the sun had scarce ever looked.
1749, Henry Fielding, chapter IV, in The History of Tom Jones, A Foundling, Book VIII1 more example
BUDGE, strong drink; […] Probably a corruption of BOOZE. Probably also, on the lucus a non lucendo principle, because its use made one incapable of budging.
1873, John Camden Hotten, The Slang Dictionary
Origin
- Latinlūcus ā nōn lūcendō
- Englishlucus a non lucendo
From Latin lūcus ā nōn lūcendō, literally "a grove from not shining", referring to Roman rhetorician Quintilian's assertion, in his Institutio Oratoria, that Latin lūcus (“grove”) derived from lūceō (“to shine”), because groves were dark places and did not shine.
More words from Latin
Full word history & related roots →Cite this entry
lucus a non lucendo. (n.d.). In WatkinsX Dictionary. Retrieved November 5, 2026, from https://dictionary.watkinsx.com/word/lucus%20a%20non%20lucendo
“lucus a non lucendo.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/lucus%20a%20non%20lucendo. Accessed November 5, 2026.
WatkinsX Dictionary, s.v. “lucus a non lucendo,” accessed November 5, 2026, https://dictionary.watkinsx.com/word/lucus%20a%20non%20lucendo.
Source: lucus a non lucendo on Wiktionary, CC BY-SA 4.0.