Almagest \Al"ma*gest\, n. [F. almageste, LL. almageste, Ar.
al-majist[imac], fr. Gr. ? (sc. ?), the greatest
composition.]
The celebrated work of Ptolemy of Alexandria, which contains
nearly all that is known of the astronomical observations and
theories of the ancients. The name was extended to other
similar works.
[1913 Webster]