almanac (n.) Look up almanac at Dictionary.com
late 14c., "book of permanent tables of astronomical data," attested in Anglo-Latin from mid-13c., via Old French almanach or directly from Medieval Latin almanachus, a word of uncertain origin and the subject of much speculation. It is probably ultimately from Arabic somehow; said in OED to be from a Spanish-Arabic al-manakh "calendar, almanac," which is possibly ultimately from Late Greek almenichiakon "calendar," which itself is said to be of Coptic origin. One-year versions, showing correspondence of days of the week and month, ecclesiastical calendars, etc., date from 16c.; "astrological and weather predictions appear in 16-17th c.; the 'useful statistics' are a modern feature" [OED].