embolismic

/ˌɛmbəˈlɪzmɪk/
adjective
  1. Relating to or inserted as an extra day or month in a calendar system (such as a leap day or intercalary month).
    • The embolismic day added to February keeps the calendar aligned with the solar year.
    • The embolismic insertion of an extra week every few years was part of the old lunisolar calendar.
    • Ancient astronomers calculated the embolismic month needed to harmonize lunar and solar cycles.
Synonyms
What does "embolismic" mean? | whatsthatwordmean | whatsthatwordmean