porpoise

鼠海豚、海豚

A group of porpoises followed the boat for several kilometers.

一群鼠海豚跟著船游了好幾公里。

上下起伏、顛躍

The speedboat porpoised across the choppy water toward the harbor.

快艇在浪濤中上下起伏，朝港口駛去。