in 1842,Britain ancient lived the scientist Charlie Germany · Irving to found “the dinosaur” this noun.English dinosaur from Greek article deinos (meaning is terror) Saurosc (meaning is lizard or reptile).Regarding Irving then,this “the terror lizard” or “the terror reptile” is the reptile which referred to a big way exterminates.In fact,discovered at that time the dinosaur are not many.After 1989 antarctica discovery dinosaur,the world seven continents had dinosaur's vestige.At present in the world the dinosaur which describes is had at least 650 to 700 many kinds of (in biology species).along with dinosaur's massive discoveries and research thorough,dinosaur's meaning had the archery target change.This essence's change is:The dinosaur was not only exterminated,the huge ancient times reptile,moreover was the ancient times reptile which could stand erect walks.Some ancient times' reptile,for instance with dinosaur same time pterodactyl,fish dragon,plesiosaurus and so on,is also huge after the animal which exterminates.But they cannot use two or four legs walk on the land,therefore they are not the dinosaur.Reptile some are the advance by creeping,walks when the abdomen clings the tread,the four limbs tries the center of resistance in body's both sides,like nowadays's turtle,alligator and so on; Some walk when the body leaves the ground slightly,but can only take the very short road,like one kind of named dragon Parker alligator's ancient times alligator,as well as modern certain alligators; Moreover is the dinosaur can equally likely in the organic evolution history the most successful place.Therefore we may say like this:The dinosaur was the life is about 23,500,000,000 to 65,000,000 year ago,can walk,already a kind of terrestrial reptile which by the hind legs support body erectness exterminated.(Shanghai Science and technology Education Publishing house "Chinese Dinosaur" author:Zhen Shuona)