dolphin

noun

dol·​phin ˈdäl-fən 

ˈdȯl-

1

a

: 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

2

: dolphinfish

3

capitalized : delphinus

4

: a spar or buoy for mooring boats

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 Web

The last time the Keys had a whale and dolphin rehabilitation facility was in the 2010s. —David Goodhue, Miami Herald, 15 Jan. 2025

Morning kayak tours are ideal for spotting dolphins, manatees, and sea turtles, while nighttime tours give an opportunity to spot bioluminescent plankton and comb jellies. —Staff Author, Southern Living, 15 Jan. 2025

The grass in front of the school and the sculpture of the school’s signature dolphin were intact while a house was burning across the street late Wednesday morning. —Howard Blume, Los Angeles Times, 8 Jan. 2025

Russia Declares Federal Emergency Over Black Sea Oil Spill By Lilith Foster-Collins News Reporter 0 A total of 32 dolphins have died in a Russian oil spill in the Kerch Strait between Crimea and Russia's southern Krasnodar region, an animal rescue group has said. —Kevin Lynn, Newsweek, 6 Jan. 2025

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)

Phrases Containing dolphin

• bottle-nosed dolphin
• bottlenose dolphin
• dolphin striker
• Risso's dolphin
• river dolphin
• spinner dolphin

Kids Definition

dolphin

noun

dol·​phin ˈdäl-fən 

ˈdȯl-

1

a

: any of various small whales with teeth and a long nose

b

: porpoise sense 1

2

: either of two active saltwater food fishes noted for their brilliant coloring