intercalate

intercalate is a   Verb

Definition:

[1] To insert, as a day or other portion of time, in a calendar.

[2] 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. Beds of fresh-water shells . . . are intercalated and interstratified with the shale. Mantell.

Synonyms: