What is "intercalate"

Intercalate \In*ter"ca*late\, v. t. [imp. & p. p. Intercalated; p. pr. & vb. n. Intercalating.] [L. intercalatus, p. p. of intercalare to intercalate to intercalate; inter between + calare to call, proclaim. See Calendar.]

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.

"to insert a day into the calendar," 1610s, from Latin intercalatus, past participle of intercalare "to proclaim the insertion of an intercalary day," from inter- "between" (see inter-) + calare (see calendar). Related: Intercalated; intercalating.

vb. 1 To insert an extra leap day into a calendar in order to maintain synchrony with natural phenomenon. 2 To insert an extra month into a calendar for the same purpose. The http://en.wikipedi

1. org/wiki/Hebrew%20calendar has such a month. 3 (context molecular biology English) To insert a substance between two or more molecules, bases, cells, or tissues.

v. insert (days) in a calendar