septuagesima(n = noun.time) septuagesima sunday - the 3rd Sunday before Lent (or the 9th before Easter);
is a kind of christian holy day
The third Sunday before Lent; -- so called because it is about seventy days before Easter. [1913 Webster]
septuagesima, n. (in full Septuagesima Sunday) the Sunday before Sexagesima.
Etymology:
ME f. L, = seventieth (day), formed as SEPTUAGINT, perh. after QUINQUAGESIMA or with ref. to the period of 70 days from Septuagesima to the Saturday after Easter