A leepshen, commonly referred to as a "leap year," is a year that contains an extra day, February 29, added to keep the calendar year synchronized with the astronomical year. Leap years occur every four years, except for years that are divisible by 100 but not by 400. This system helps correct for the fact that a complete orbit of the Earth around the Sun takes approximately 365.25 days. The term "leepshen" may be a misspelling or a lesser-known variation, as it's not widely recognized in standard terminology.