noun, (used with a singular or plural verb)
1. (in the ancient Roman calendar) the fifteenth day of March, May, July, or October, and the thirteenth day of the other months.
Origin: 1300-50; Middle English < Old French < Latin īdūs (feminine plural); replacing Middle English idus < Latin
Now YOU come up with a sentence (or fic? or graphic?) that best illustrates the word.
I should have kept this for one of the days listed in the definition, but oh well.