sinusoid

Any curve of the form $y = A\sin(B(x-C)) + D$ , or the cosine equivalent.

A sinusoid is any curve of the form $y=A\sin(B(x-C))+D$ (or the equivalent with cosine) — a sine or cosine wave with its height, timing, and position controlled by the four constants $A$ , $B$ , $C$ , $D$ . Anything with a restoring force pulling it back toward a center position — a spring, a pendulum, a tide — oscillates sinusoidally.