A dinosaur is defined as any of the large, extinct reptiles that roamed Earth during the Paleozoic and Mesozoic eras.(noun)
An example of a dinosaur is the Brontosaurus.
The definition of a dinosaur is someone who resists change or is old-fashioned.(noun)
An example of a dinosaur is the person in the office who still sends messages by fax.
See dinosaur in Webster's New World College Dictionary
Origin: dino- + -saur
See dinosaur in American Heritage Dictionary 4
Origin: New Latin Dīnosauria, group name
Origin: , from Dīnosaurus, former genus name
Origin: : Greek deinos, monstrous
Origin: + Greek sauros, lizard.
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