calendar vs intercalation

calendar and intercalation both are nouns.

Word	Noun	Adjective	Verb	Adverb
calendar	Yes	No	Yes	No
intercalation	Yes	No	No	No

calendar (noun)	intercalation (noun)
a list or register of events (appointments or social events or court cases etc)	an insertion into a calendar
a tabular array of the days (usually for one year)
a system of timekeeping that defines the beginning and length and divisions of the year

calendar (verb)	intercalation (verb)
enter into a calendar