Definition of "dolphin" []

• Any of various marine cetacean mammals, such as the bottle-nosed dolphin, of the family Delphinidae, related to the whales but generally smaller and having a beaklike snout. (noun)
• A large marine food and game fish (Coryphaena hippurus) found worldwide in tropical waters, having an iridescent blue back, yellow sides, a steep blunt forehead, and a long continuous dorsal fin. Also called dolphinfish, dorado, mahi-mahi. (noun)
• A similar fish (C. equisetis) of smaller size, having silvery or pale yellow sides. Also called dolphinfish, pompano dolphin. (noun)
• A buoy, pile, or group of piles used for mooring boats. (noun)
• A group of piers used as a fender at a dock. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "We use the term dolphin to refer to members of the taxonomic family Delphinidae, which consists of thirty-three species of dolphins ranging from coastal to pelagic and tiny to large."
• "Captivity for a dolphin is a life-long imprisonment."
• "But why then, if a dolphin is an intelligent agent, would we not include the dolphin as a likely candidate?"