In·ter·ca·late v. t. [imp. & p. p. Intercalated p. pr. & vb. n. Intercalating ]
  1. Chron. 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.
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