ground swell
heavy swell

The timing in the heavy swell had to be carefully judged.

However, there was a heavy swell and she filled with water within 10 minutes.

It was like traveling by ship on a heavy swell.

"All they're going to get out of it are some heavy swells."

A new day showed heavier swells than those of night.

Due to the heavy swell, one of the horses fell over.

It did not break up immediately, and the heavy swell made evacuation impossible until 18 June.

There was quite a heavy swell on, and the ocean did not appear very attractive.

A heavy swell came at them out of the thick darkness.

The boat loomed up on the heavy swell, close to him.