D defs.my
Entry 2 senses Webster, 1913

Intercalate

· In·ter·ca·late · IPA /ɪnˈtɝ.kəˌleɪt/
01 v. t. To insert, as a day or other portion of time, in a calendar.
imp. & p. p. Intercalated; p. pr. & vb. n. Intercalating
  1. 1.
    To insert, as a day or other portion of time, in a calendar.(Chron.)
  2. 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.(Geol.)
    “Beds of fresh-water shells . . . are intercalated and interstratified with the shale.” — Mantell.