[in-tur-kuh-ley-shuh
n] 
| 1. | the act of intercalating; insertion or interpolation, as in a series. |
| 2. | something that is intercalated; interpolation. |
| in·ter·ca·late (ĭn-tûr'kə-lāt') tr.v. in·ter·ca·lat·ed, in·ter·ca·lat·ing, in·ter·ca·lates
[Latin intercalāre, intercalāt- : inter-, inter- + calāre, to proclaim; see kelə-2 in Indo-European roots.] in·ter'ca·la'tion n., in·ter'ca·la'tive adj. |
intercalation
insertion of days or months into a calendar to bring it into line with the solar year (year of the seasons). One example is the periodic inclusion of leap-year day (February 29) in the Gregorian calendar now in general use. To keep the months of a lunar calendar (e.g., the Hindu calendar) in their proper seasons, an entire month must be intercalated periodically, because there are a fractional number (between 12 and 13) of cycles of lunar phases (months) in a solar year. In cultures without highly developed astronomy, intercalation was done empirically, whenever seasons and their properly associated months became noticeably out of step.
Learn more about intercalation with a free trial on Britannica.com.