computus

• compotus, conpotus

Borrowed from Latin computus. Doublet of conto.

computus (countable and uncountable, plural computi)

1. The calculation of the date of Easter in the Christian calendar.
   • 2008, Ian F. McNeely, Lisa Wolverton, Reinventing Knowledge: From Alexandria to the Internet, page 68:

     An elaborate bundle of techniques called computus therefore developed around Easter calculations. Computus formed the centerpiece of “scientific” education in the monasteries.

   • 2011, Elisheva Carlbach, Palaces of Time, page 11:

     Bede's work, which remained in active use for half a millennium, stood at the very center of the university curriculum, because the mastery of computus included many different essential subjects such as astronomy, mathematics, geography, theology, and law; its applications, too, included medicine and agriculture.

   • 2011, C. Philipp E. Nothaft, Dating the Passion: The Life of Jesus and the Emergence of Scientific Chronology (200-1600), page 103:

     The technical problems faced by Western computists when it came to dating the day of Christ's Passion and the year of the world's creation were so persistent and perplexing that only a radical solution could restore the lost coherence of computus and chronography.

2. (historical) A book of tables for calculating dates of astronomical events and moveable feasts.
   • 1987, Bruce Eastwood, 5: Plinian astronomical diagrams in the early Middle Ages, Edward Grant, John Emery Murdoch, Mathematics and Its Applications to Science and Natural Philosophy in the Middle Ages, page 149,

     This computus also contains only one completed Plinian diagram, that for the planetary harmonic intervals.

   • 2007, László Sándor Chardonnens, Anglo-Saxon Prognostics, 900-1100: Study and Texts, page 25:

     Prognostics have thus been discovered in computi, in volumes on science or medicine, and in miscellanies which present a host of different text genres.

• compute
• computist

• almanac

• compotus
• conpotus

From computō.

computus m (genitive computī); second declension

1. (Late Latin) computation, calculation
2. (Late Latin) bank account

Second-declension noun.

• “computus”, in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
• computus in Charles du Fresne du Cange’s Glossarium Mediæ et Infimæ Latinitatis (augmented edition with additions by D. P. Carpenterius, Adelungius and others, edited by Léopold Favre, 1883–1887)
• computus in Gaffiot, Félix (1934) Dictionnaire illustré latin-français, Hachette.