from
The Collaborative International Dictionary of English v.0.48
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}.]
[1913 Webster]
1. (Chron.) To insert, as a day or other portion of time, in
a calendar.
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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.
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Beds of fresh-water shells . . . are intercalated
and interstratified with the shale. --Mantell.
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