ἐμβολισμός, in Chronology, signifies "intercalation." The word is formed of ἐμβάλλων, "to inset."

As the Greeks made use of the lunar year, which is only 354 days; in order to bring it to the solar, which is 365 years, they had every two or three years an embolism, i.e., they added a 13th lunar month every two or three years, which additional month they called embolismicus, ἐμβολικός, because inserted, or intercalated.