From Longman Dictionary of Contemporary Englishdolphindol‧phin /ˈdɒlfɪn $ ˈdɑːl-, ˈdɒːl-/ ●●○ noun [countable] 
HBAa very intelligent sea animal like a fish with a long grey pointed nose
HBAa very intelligent sea animal like a fish with a long grey pointed noseExamples from the Corpus
dolphin• It was not a black man, just a dolphin.• For apart from being equipped with eyes, head and body, dolphins and whales bear little outward physical resemblance to ourselves.• Net-caught dolphins frequently have lungs filled with water.• It was a dorado or dolphin fish, a voracious predator which feeds mostly on flying fish.• Surely not ... She ran upstairs again, heedless of the dolphin thrashing wetly on the upper landing.• The dolphins were trained to use pressurized canisters to shoot intruders with a.45 calibre bullets at point-blank range.• If a more decorative fountain is required, an ornamental fountain, such as this dolphin one, can be installed.• Furthermore, the public is told that ail similarities to dolphins are purely coincidental.Origin dolphin (1300-1400) Old French dalfin, from Greek delphis 