The adjective is a learned borrowing from Latin pellūcidus, perlucidus (“transparent, pellucid; very bright; very understandable”), from per- (prefix meaning ‘through; throughout; completely, thoroughly’) + lūcidus (“clear; full of light, bright, shining; (figuratively) easily understood, clear, lucid”) (from lūceō (“to shine; to become visible, show through; (figuratively) to be apparent, conspicuous, or evident”) (ultimately from Proto-Indo-European *lewk- (“bright; to see; to shine”)) + -idus (suffix meaning ‘tending to’ forming adjectives)). The noun is derived from the adjective. Cognates * Late Latin pellucidum (“transparent substance”) * Middle French pellucide (modern French pellucide (“pellucid”))
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Literary Allowing the passage of light; translucent or transparent.
Blood to the naked Eye appears all red; but by a good Microſcope, vvherein its leſſer parts appear, ſhevvs only ſome fevv Globules of Red, ſvvimming in a pellucid Liquor; and hovv theſe Globules vvould appear, if Glaſſes could be found, that yet could magnifie them 1000, or 10000 times more, is uncertain.1689 (indicated as 1690), [John Locke], “Of Our Complex Ideas of Substances”, in An Essay Concerning Humane Understanding. […], London: […] Eliz[abeth] Holt, for Thomas Basset, […], →OCLC, book II, § 11, page 140:
This Cryſtal is a pellucid fiſſile Stone, clear as VVater or Cryſtal of the Rock, and vvithout Colour; enduring a red Heat vvithout loſing its tranſparency, and in a very ſtrong Heat calcining vvithout Fuſion.a. 1728 (date written), Isaac Newton, “[The Third Book of Opticks.] [Qu[estion] 25. Are there not other original Properties of the Rays of Light, besides those already described?]”, in Opticks: Or, A Treatise of the Reflections, Refractions, Inflections and Colours of Light. […], 4th edition, London: […] William Innys […], published 1730, →OCLC, page 329:
4 more examples
As a stream, clear and bright, becomes foul with weeds, and stagnates by its distant meanderings from its pure and pellucid source,—so the active imagination, the capacious intellect of Douglas, those high and valuable endowments, had, by an undue use of them, been perverted.1838, [Letitia Elizabeth] Landon (indicated as editor), Duty and Inclination: […], volume III, London: Henry Colburn, […], →OCLC, pages 308–309:
The sea was shining like a sheet of glass, […] and the bright sea-weeds and the brilliant corals shone in the depths of that pellucid water, as we rowed over it, like rare and precious gems.1857, Robert Michael Ballantyne, chapter XVI, in The Coral Island: A Tale of the Pacific Ocean, Boston, Mass.: Phillips, Sampson, and Company, published 1859, →OCLC, page 147:
You cannot think what figs / My teeth have met in, / What melons icy-cold / Piled on a dish of gold / Too huge for me to hold, / What peaches with a velvet nap, / Pellucid grapes without one seed: […]1862, Christina Rossetti, “Goblin Market”, in Goblin Market and Other Poems, Cambridge, Cambridgeshire; London: Macmillan & Co., […], →OCLC, page 10:
The thick vegetation met overhead, interlacing into a natural pergola, and through this tunnel of verdure in a golden twilight flowed the green, pellucid river, beautiful in itself, but marvelous from the strange tints thrown by the vivid light from above filtered and tempered in its fall.1912, Arthur Conan Doyle, “‘The Outlying Pickets of the New World’”, in The Lost World […], London; New York, N.Y.: Hodder and Stoughton, →OCLC, pages 119–120:
Written in spare, pellucid prose, the book reads like a close-to-the-bone memoir.1994 November 13, Fritz Lanham, The Houston Chronicle, Houston, Tex.: Houston Chronicle Pub. Co., →ISSN, →OCLC:
[Y]ou never receive me apart from the grammar that establishes my availability to you. If I treat that grammar as pellucid, then I fail to call attention precisely to that sphere of language that establishes and disestablishes intelligibility, and that would be precisely to thwart my own project as I have described it to you here.1999, Judith Butler, “Preface (1999)”, in Gender Trouble: Feminism and the Subversion of Identity, New York, N.Y.; Abingdon, Oxon., published 2015, →ISBN, page xxvi:
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Figuratively, Literary Of music or some other sound: not discordant or harsh; clear and pure-sounding.
Opera star [Giorgio] Tozzi sings with the richness of burnished bronze and [Sharon] Daniels complements him with her pellucid soprano.1979 October 22, T. E. Kalem, “Theater: Monopod”, in Henry R[obinson] Luce, editor, Time, New York, N.Y.: Time Inc., →ISSN, →OCLC, archived from the original on 12 Sep 2022:
4
Figuratively, Literary Of a person, their mind, etc.: able to think and understand clearly; not confused; clear, sharp.
The adjective is a learned borrowing from Latin pellūcidus, perlucidus (“transparent, pellucid; very bright; very understandable”), from per- (prefix meaning ‘through; throughout; completely, thoroughly’) + lūcidus (“clear; full of light, bright, shining; (figuratively) easily understood, clear, lucid”) (from lūceō (“to shine; to become visible, show through; (figuratively) to be apparent, conspicuous, or evident”) (ultimately from Proto-Indo-European *lewk- (“bright; to see; to shine”)) + -idus (suffix meaning ‘tending to’ forming adjectives)). The noun is derived from the adjective. Cognates * Late Latin pellucidum (“transparent substance”) * Middle French pellucide (modern French pellucide (“pellucid”))
1
Literary, Obsolete, Rare Something which allows the passage of light; a translucent or transparent object.
A Pellucid is not ſeen, but percieved^([sic]) by the privation of Colour. So vve ſee not Air in Air, VVater in VVater, Glaſs in Glaſs, and every Pellucid in an equal Pellucid; and becauſe vve knovv they are not coloured, vve count them to be diaphanous, viz. that may be ſeen, or ſhone thorough.1729, [Johann Jacob Hainlin], “Of the Vision of Pellucidity or Shining through”, in Venterus Mandey, transl., Synopsis Mathematica Universalis: Or, A Brief System of Mathematics, […], [3rd] edition, London: […] A. Ward, […], →OCLC, paragraph 1, page 686:
The true Aſtroites, vvhich in the ſun-ſhine throvvs out a briſk light radiating from one certain point, belongs to the claſs of Pellucids.[1735?], Herman Boerhaave, “Being a Delineation of the Theory. [Of Stones.]”, in [anonymous], transl., Elements of Chemistry. Being the Annual Lectures of Hermann Boerhaave, M.D. […], volume I, London: […] J. Clarke […], and S. Austen […]; and sold by J. Roberts […], →OCLC, page 33: