[ dol-fin, dawl- ]
See synonyms for dolphin on
  1. any of several chiefly marine, cetacean mammals of the family Delphinidae, having a fishlike body, numerous teeth, and the front of the head elongated into a beaklike projection.

  2. Also called dolphinfish, mahimahi, pompano dolphin . either of two large, slender fishes, Coryphaena hippurus or C. equisetis, of warm and temperate seas.

  1. Nautical.

    • a pile, cluster of piles, or buoy to which a vessel may be moored in open water.

    • a cluster of piles used as a fender, as at the entrance to a dock.

    • a pudding fender at the nose of a tugboat or on the side of a vessel.

  2. Dolphin, Astronomy. the constellation Delphinus.

Origin of dolphin

First recorded in 1300–50; Middle English dolphyn, from Old French daulphin, from Old Provençal dalfin, from unattested Vulgar Latin dalfīnus, Latin delphīnus, from Greek delphī́n

Words Nearby dolphin Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use dolphin in a sentence

British Dictionary definitions for dolphin


/ (ˈdɒlfɪn) /

  1. any of various marine cetacean mammals of the family Delphinidae, esp Delphinus delphis, that are typically smaller than whales and larger than porpoises and have a beaklike snout

  2. river dolphin any freshwater cetacean of the family Platanistidae, inhabiting rivers of North and South America and S Asia. They are smaller than marine dolphins and have a longer narrower snout

  1. Also called: dorado either of two large marine percoid fishes, Coryphaena hippurus or C. equisetis, that resemble the cetacean dolphins and have an iridescent coloration

  2. nautical a post or buoy for mooring a vessel

Origin of dolphin

C13: from Old French dauphin, via Latin, from Greek delphin-, delphis

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012