almanac

\ \ [14] One of the first recorded uses of almanac in English is by Chaucer in his Treatise on the astrolabe 1391: ‘A table of the verray Moeuyng of the Mone from howre to howre, every day and in every signe, after thin Almenak’. At that time an almanac was specifically a table of the movements and positions of the sun, moon, and planets, from which astronomical calculations could be made; other refinements and additions, such as a calendar, came to be included over succeeding centuries. The earliest authenticated reference to an almanac comes in the (Latin) works of the English scientist Roger Bacon, in the mid 13th century. But the ultimate source of the word is obscure. Its first syllable, al-, and its general relevance to medieval science and technology, strongly suggest an Arabic origin, but no convincing candidate has been found.