This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

v. To insert (a day or month) in a calendar.

v. To insert, interpose, or interpolate.

v. To insert an extra, leap, day into a calendar in order to maintain synchrony with natural phenomena.

v. To insert an extra month into a calendar for the same purpose. The Hebrew calendar has such a month.

v. To insert a substance between two or more molecules, bases, cells, or tissues.

v. To insert, as a day or other portion of time, in a calendar.

v. To insert among others, as a verse in a stanza; specif. (Geol.), to introduce as a bed or stratum, between the layers of a regular series of rocks.

In chronology, to insert in the calendar by proclamation or authority, as an extra day or month. See intercalary, 1.

Hence To insert between others; introduce interstitially; interject or interpolate, as something irregular or unrelated.

v. insert (days) in a calendar

"I think it is necessary that the indian people, of which I am a member, should contribute with its science and its knowledge to human development because we have enormous potentials and we could intercalate our very ancient heritage with the achievements of the civilization in Europe as well as in other parts of the world."

intercalated    intercalates    intercalating   

add   

bissextile year    bissextile    bissextile month   

intercalated    intercalating    intercalation    intercalary   

insert