Etymologically
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perpendiculum

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Pronunciation

  • Classical: [pɛr.pɛnˈdɪ.kʊ.ɫũː][1]
  • Ecclesiastical: [per.penˈdiː.ku.lum][1]

Forms

perpendiculum n (genitive perpendiculī); second declension[1] A masculine perpendiculus occurs in Frontinus' writings on land surveying.[2][3]

Etymology

It is from Latin perpendō (“to weigh carefully”) + -culum, a noun of instrument.[2][1][3] De Vaan lists it among the derivatives of pendō (“to hang, weigh”), which goes back to Proto-Italic *pend-e/o- (“to hang”) and Proto-Indo-European *(s)pend-e/o- (“to spin”).[4] Isidore of Seville explains it as what always hangs down.[3]

Earliest recorded meaning

De Vaan records it first in Cato,[4][5] who prescribes in De agri cultura that a small post should stand upright in the middle ad perpendiculum, “vertically”.[2]

Semantic evolution

It names the plumb line: Cicero speaks of testing columns by the plumb line, and of using plumb line and cord;[2][6] Vitruvius, Pliny the Elder and Apuleius use it in building and in measuring heights.[2][6] From the instrument it came to mean the vertical line or plane itself, as in Vitruvius.[2] The phrase ad perpendiculum, “vertically”, is the commonest use, as in Cicero's De fato of bodies falling by their weight and in Caesar of timbers not set vertically but slanting.[2] Ausonius uses it figuratively of someone who kept himself and his family strictly in line.[7] Medieval writers in Britain use it for the plumb line, a mason's rule, the perpendicular, and a pothook.[8]

Timeline

  • 234–149 BC – Cato uses ad perpendiculum for “vertically”.[2][4][5]
  • 81–43 BC – Cicero uses it of the plumb line.[2][5]
  • c. 84–c. 25 BC – Vitruvius uses it of the vertical line or plane.[2][5]
  • c. 310–394 AD – Ausonius uses it figuratively of strict order.[7][5]
  • Medieval Latin – It also names a mason's rule and a pothook.[8]

Meanings

Noun

  1. A plumb line, plummet.[2][6]
  2. A vertical line or plane, a perpendicular.[2]
  3. ad perpendiculum: vertically, perpendicularly.[2][6]
  4. (Medieval Latin) A mason's rule, carpenter's square.[8]
  5. (Medieval Latin) A pothook.[8]

References

  1. ^ a b c d Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ 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
  3. ^ a b c Thesaurus linguae Latinae (1900–), Leipzig: Teubner; Berlin: De Gruyter; open-access ed., Munich: Bayerische Akademie der Wissenschaften
  4. ^ 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
  5. ^ a b c d e Köbler, Gerhard (2010), Lateinisches Abkunfts- und Wirkungswörterbuch für Altertum und Mittelalter, online ed., koeblergerhard.de
  6. ^ a b c d Lewis, Charlton T.; Short, Charles (1879), A Latin Dictionary, Oxford: Clarendon Press
  7. ^ a b Georges, Karl Ernst (1913–1918), Ausführliches lateinisch-deutsches Handwörterbuch, 8th ed., ed. Heinrich Georges, Hannover; Leipzig: Hahn
  8. ^ a b c d Latham, R. E., D. R. Howlett, R. K. Ashdowne, et al. (1975–2013), Dictionary of Medieval Latin from British Sources, London: British Academy / Oxford University Press