porpoise (plural porpoises)
- A small cetacean of the family Phocoenidae, related to dolphins and whales.
- (North America, imprecisely) Any small dolphin.
- French: marsouin
- German: Tümmler, Schweinswal
- Italian: focena
- Portuguese: toninha
- Russian: морска́я свинья́
- Spanish: marsopa
porpoise (porpoises, present participle porpoising; past and past participle porpoised)
- (intransitive) Said of an air-breathing aquatic animal such as a porpoise or penguin: To repeatedly jump out of the water to take a breath and dive back in a continuous motion.
- (intransitive) Said of an aircraft: to make a series of plunges when taking off or landing; or of a watercraft: to successively plunge up and down in the water.