: any of various small marine toothed whales (family Delphinidae) with the snout more or less elongated into a beak and the neck vertebrae partially fused
Note:
While not closely related, dolphins and porpoises share a physical resemblance that often leads to misidentification. Dolphins typically have cone-shaped teeth, curved dorsal fins, and elongated beaks with large mouths, while porpoises have flat, spade-shaped teeth, triangular dorsal fins, and shortened beaks with smaller mouths.
b
: any of several related chiefly freshwater toothed whales (as of the families Platanistidae and Iniidae) : river dolphin
also: a cluster of closely driven piles used as a fender for a dock or as a mooring or guide for boats
Illustration of dolphin
dolphin 1a
Examples of dolphin in a Sentence
Recent Examples on the WebChoose a morning sail to look for dolphins and other wildlife, or book an evening cruise to catch sunset at its peak.—Kaitlyn Yarborough, Southern Living, 13 July 2024 SeaWorld San Antonio welcomed two new babies after recent births at the park: a Pacific white-sided dolphin and a beluga whale.—Megan Stringer, Axios, 12 July 2024 The remaining days include more secluded islands and plenty of wildlife viewing — depending on the season, guests can see gray, fin, blue, orca, and sperm whales, along with hundreds of dolphins and many species of birds.—Patricia Doherty, Travel + Leisure, 10 July 2024 Plastic bags are among the most common types of plastic waste consumed by or entangling marine animals, including the endangered Pacific leatherback sea turtles, whales and dolphins.—Fiona Hines, The Mercury News, 6 July 2024 See all Example Sentences for dolphin
These examples are programmatically compiled from various online sources to illustrate current usage of the word 'dolphin.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
Word History
Etymology
Middle English delphyn, dolphyn, from Anglo-French delphin, alteration of Old French dalfin, from Medieval Latin dalfinus, alteration of Latin delphinus, from Greek delphin-, delphis; akin to Greek delphys womb, Sanskrit garbha
First Known Use
14th century, in the meaning defined at sense 1a(1)
Time Traveler
The first known use of dolphin was
in the 14th century
Share