wave

A moving ridge of water, especially on the surface of the sea.

"The boat was tossed by a large wave."

To move one's hand or arm to greet or signal to someone.

"She waved goodbye from the platform."

A slight curl or curve in hair.

"She had a natural wave in her hair."

A disturbance that transfers energy through a medium or space.

"Radio waves transmit signals across distances."