cyclical
adjective uk/ˈsɪk.lɪ.kəl/ /ˈsaɪ.klɪ.kəl/ us/ˈsɪk.lɪ.kəl/ /ˈsaɪ.klɪ.kəl/ (also cyclic, /ˈsɪk.lɪk/ /ˈsaɪ.klɪk/ /ˈsɪk.lɪk/ /ˈsaɪ.klɪk/)
循环的；周期性的
Cyclical events happen in a particular order, one following the other, and are often repeated.
Changes in the economy have followed a cyclical pattern. 经济呈周期性变化。