unit: [16] The term unit was given general currency by the 16th-century English mathematician, astrologer, and magician John Dee. It was formed from Latin ūnus, probably on the analogy of digit, and used as a mathematical term to replace unity as a translation of Euclid’s monás ‘indivisible number’. In a comment added to his introduction to Sir Henry Billingsley’s translation of Euclid, Dee wrote ‘Note the word unit to express the Greek monas, and not unity: as we have all commonly until now used’.
