having a succession of waves or curves

Refers to the even waveform of an alternating current.

A waveform in which the rate of change of a signal varies from zero to a maximum value in a smooth and regular manner that is described by the trigonometric sine function.

Varying in proportion to the sine of an angle or time function. AC voltage in which the instantaneous value is equal to the sine of the phase angle times the peak value.

Having a magnitude that varies as the sine of an independent variable. A sinusoidal wave is a sine wave. The image below shows a sine wave and a square wave.