ides

• POS: Noun

CIDE DICTIONARY

ides, n. pl. [L. idus: cf. F. ides.].

 The fifteenth day of March, May, July, and October, and the thirteenth day of the other months.  [1913 Webster]
" Eight days in each month often pass by this name, but only one strictly receives it, the others being called respectively the day before the ides, and so on, backward, to the eighth from the ides."  [1913 Webster]
"The ides of March remember."  [1913 Webster]

OXFORD DICTIONARY

ides, n.pl. the eighth day after the nones in the ancient Roman calendar (the 15th day of March, May, July, October, the 13th of other months).

Etymology

ME f. OF f. L idus (pl.), perh. f. Etruscan