epochal adj : highly significant or important especially bringing about or marking the beginning of a new development or era; "epochal decisions made by Roosevelt and Churchill"; "an epoch-making discovery" [syn: epoch-making]

English

Adjective

1. of or pertaining to an epoch
2. highly important or significant; monumentous, epoch-making

alternate, beating, circling, consequential, cyclic, even, every other, far-reaching, important, intermittent, isochronal, measured, metronomic, momentous, oscillatory, periodical, pulsing, reciprocal, recurrent, recurring, rhythmic, rotary, seasonal, serial, steady, undulant, undulatory, unmatched, unparalleled, wavelike, wheeling