Etymologically
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planus

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Pronunciation

  • IPA (Classical): [ˈpɫaː.nʊs][1]
  • IPA (Ecclesiastical): [ˈplaː.nus][1]

Forms

plānus (feminine plāna, neuter plānum, comparative planior, superlative planissimus, adverb plānē); first/second-declension adjective[1]

Etymology

It is inherited from Proto-Italic *plāno-, inherited from Proto-Indo-European *pl̥h₂-nó- (“flattened”), from the root *pleh₂- (“flat”).[2][1]

Cognate with Hittite palhi- (“wide, broad”), Old Prussian plonis (“threshing floor”), Lithuanian plónas (“thin”) and Latvian plãns (“flat, even, thin”).[2] The OLD also compares English floor.[3]

Earliest recorded meaning

It is found from Plautus onwards,[2][4] who speaks of an easy and level road, facilis et plana via.[5]

Semantic evolution

It described level ground and calm water, a house on ground level, and anything flat, so that plana manu was “with the flat of the hand” and piscis planus a flatfish.[3] Cicero used it in geometry, naming the circle the finest of plane figures.[3]

Of speech it meant plain and straightforward, and more often clear or obvious: planum facere was to make something clear or prove it.[3] Medieval Latin used it for land that was not wooded, in the phrase in bosco et plano, “in woods and fields”,[6] and in music for a chant in a low register.[7] It survives as Italian piano, Old French plain, Spanish llano and Portuguese chão.[1] English plain came from Old French about 1300, and plane was taken from Latin planum about 1600.[8]

Timeline

  • c. 250–184 BC – Plautus uses it of a level road.[5][4]
  • 234–149 BC – Cato uses it of a flat surface.[3][4]
  • 81–43 BC – Cicero uses it of plane figures in geometry.[3][4]
  • c. 1300 – English plain is borrowed from Old French.[8]
  • c. 1600 – English plane “flat surface” is taken from Latin.[8]

Meanings

Adjective

  1. Level, flat, even, (of water) calm.[3][5]
  2. On ground level.[3]
  3. Having a flat surface, plana manu with the flat of the hand.[3]
  4. (geometry) plane, two-dimensional.[3]
  5. (of speech) Plain, simple.[3]
  6. Clear, obvious, planum facere to make clear, prove.[3][1]
  7. (Medieval Latin) Not wooded, open.[6]

Word family

  • planaris
  • plānārius
  • implanus
  • perplānus
  • plāna
  • plāniloquus
  • plānipēs
  • plānitās
  • plānitia
  • plānitiēs
  • planitudo
  • plānum

Usage notes

A different word, planus with a short a, from Greek Ancient Greek πλάνος (plános), meant a vagabond or impostor, a word Cicero and Horace use.[3][5][4]

References

  1. ^ a b c d e f Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ a b c de Vaan, Michiel (2008), Etymological Dictionary of Latin and the other Italic Languages, Leiden Indo-European Etymological Dictionary Series 7, Leiden; Boston: Brill
  3. ^ a b c d e f g h i j k l m Glare, P. G. W., ed. (2012), Oxford Latin Dictionary, 2nd ed., Oxford: Oxford University Press
  4. ^ a b c d e Köbler, Gerhard (2010), Lateinisches Abkunfts- und Wirkungswörterbuch für Altertum und Mittelalter, online ed., koeblergerhard.de
  5. ^ a b c d Lewis, Charlton T.; Short, Charles (1879), A Latin Dictionary, Oxford: Clarendon Press
  6. ^ a b Niermeyer, J. F. (1976), Mediae Latinitatis Lexicon Minus, Leiden: Brill
  7. ^ Lexicon musicum Latinum medii aevi (1992–), Munich: Bayerische Akademie der Wissenschaften; online ed. Wörterbuchnetz
  8. ^ a b c Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com