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noun \ˈē-ˌpakt, ˈe-\

Definition of epact

  1. :  a period added to harmonize the lunar with the solar calendar

Origin and Etymology of epact

Middle French epacte, from Late Latin epacta, from Greek epaktē, from epagein to bring in, intercalate, from epi- + agein to drive — more at agent

First Known Use: 1588

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