Intercalation
Pronunciation : In*ter`ca*la"tion
Part of Speech : n.
Etymology : [L. intercalatio: cf. F. intercalation.]
Definition : 1. (Chron.)
Defn: The insertion of a day, or other portion of time, in a calendar.
2. The insertion or introduction of anything among others, as the insertion of a phrase, line, or verse in a metrical composition; specif. (Geol.), the intrusion of a bed or layer between other layers. Intercalations of fresh-water species in some localities. Mantell.
Source : Webster's Unabridged Dictionary, 1913