periodic
Cross references:
1. intermittent
pe.ri.od.ic \.pir-e--'a:d-ik\ aj 1a: occurring at regular intervals 1b:
RECURRENT 2: consisting of or containing a series of repeated stages :
CYCLICM {~ decimals} 3: of or relating to a period 4: expressed in or
characterized by periodic sentences
Webster's English Dictionary