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

Carden invites on comedians like Bowen Yang, Kumail Nanjiani, and Ellie Kemper for a sort of quiz show drawing from the bizarre facts of Wikipedia's depths, from dolphins to Ancient Rome to Lenny Kravitz. —Eliana Dockterman, TIME, 31 May 2024

The San Diego Union-Tribune has chosen to introduce you to 10 researchers whose work ranges from literally taking the planet’s temperature to exploring how dolphins communicate. —Gary Robbins, San Diego Union-Tribune, 26 May 2024

The few people who choose to live there are vastly outnumbered by sheep, rabbits and the whales and dolphins that frolic in the cobalt seas surrounding the rocky coast line. —Kate Duffy, Fortune Europe, 24 May 2024

Diana Reiss, a marine mammal behavior and communication expert at the City University of New York, said that scientists understand certain aspects of marine animals’ communication reasonably well, including the whistles used by dolphins and the songs sung by humpback whales. —Maria Cheng, The Christian Science Monitor, 8 May 2024

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