A "porpoise" is a type of small marine mammal that is similar to a dolphin. It has a curved fin on its back and is known for being playful and intelligent. Full definition
Two years ago, a report in Nature suggested that pingers, which emit periodic high - frequency underwater bursts, had markedly reduced the accidental catch of harbor porpoises in the Gulf of Maine's groundfish fishery. (sciencemag.org)
At this peninsula it's not rare to catch sight of porpoises leaping in the water. (visitstaugustine.com)
Our first marine mammal encounter of the tour was a group of 8 - 10 harbour porpoise in Johnstone Strait. (stubbs-island.com)