almagest noun.
['almǝdʒɛst] Also
Almagest.
LME.[Old French almageste ult. from Arab. al-mijistī, formed as AL-2 + Greek megistē greatest (sc. composition).]A great astronomical treatise by Ptolemy (translated into Arabic in the 9th cent.); any of various other early textbooks of astrology and alchemy.
[TahlilGaran] English Dictionary ▲