Alternative forms 
Old French almanach, from Medieval Latin almanachus, from Andalusian Arabic (almanak, “almanac, calendar”), from Arabic المناخ (al-manāx, “climate”), from Late Ancient Greek ἀλμενιχιακά (“calendar”), probably ultimately of Coptic origin. Possibly the central syllable -man- is cognate with moon and month, or else was influenced by Proto-Indo-European *mens- (“moon, month”), from Proto-Indo-European base *me- (to measure).
almanac (plural almanacs)
- (astronomy, navigation) A book or table listing nautical, astronomical, astrological or other events for the year; sometimes, but not essentially, containing historical and statistical information.