intercalate UK /ɪnˈtɜː.kəl.eɪt/US /ɪnˈtɝ.kəˌleɪt/verb 4noun 2forms 3 verb4 •To insert an extra leap day into a calendar in order to maintain synchrony with natural phenomena.'[T]is wonderful where or when we ever got anything of this which we call wisdom, poetry, virtue. We never got it on any dated calendar day. Some heavenly days must have been intercalated somewhere. — 1844 •To insert an extra month into a calendar for the same purpose, such as for the Hebrew calendar. •To insert a substance between two or more molecules, bases, cells, or tissues. •To insert anything somewhere (especially between other things), such as an affix into a word. (Compare interpolate.)Sometimes f or s is intercalated to lighten the pronunciation : kommen, Kunft ; können, Kunst ; […] — 1894 noun2 •[before a noun] An atom or molecule, or a substance, that enters between the layers of the crystal lattice of another substance, especially that of graphite. •A compound formed by foreign atoms or molecules entering between the layers of a crystal lattice, especially that of graphite. formsintercalated · intercalating · intercalates