periodic

I adjective cadenced, cadent, continual, cyclic, cyclical, erratic, fluctuating, frequent, habitual, intermittent, measured, occasional, occurring again, oft-repeated, oftentime, patterned, perpetual, reappearing, recurrent, recurring, regular, regulated, remittent, repeated, returning, returning at intervals, rhythmic, rhythmical, seasonal, serial, sollemnis, spasmodic, sporadic, successive, systematic, variable II index disjunctive (tending to disjoin), habitual, infrequent, intermittent, regular (orderly), repeated, sporadic