Epidemiologists use "waves" to describe the sustained rise and fall of infections (such as COVID-19), distinct from a momentary "spike" [PMC].
From the quantum wavefunction that describes the probability of an electron's location, to the massive gravitational waves (ripples in spacetime) recently detected by LIGO, the wave is the primary mechanism by which the universe communicates energy and information. Epidemiologists use "waves" to describe the sustained rise