metemptosis, n. [NL., from Gr. beyond, after + a falling upon, fr. to fall in or upon; in + to fall.].
The suppression of a day in the calendar to prevent the date of the new moon being set a day too late, or the suppression of the bissextile day once in 134 years. The opposite to this is the proemptosis, or the addition of a day every 330 years, and another every 2,400 years. [1913 Webster]