When something happens cyclically, it does not happen just once. It comes back again and again in the same order, like a wheel that keeps turning. The year does this: spring, summer, autumn, winter — then spring again. People also say prices, sleep, or even a bad mood move cyclically when they go up and down in a repeating pattern. Though actually, this is a rather school-and-report word. In ordinary talk someone is more likely to say “it keeps happening in cycles” or “it comes round again.” And it is about time repeating, not about drawing a circle on a page. A fan can spin in a circle; the seasons change cyclically.