What is the meaning of Dinosaur?

Those animals of the clade Dinosauria that existed during the Triassic, Jurassic and Cretaceous periods and are now extinct; that is, any member of the clade Dinosauria other than birds. 

Any of the animals belonging to the clade Dinosauria, including all non-avian dinosaurs (all extinct) and all birds (extant or extinct).

Any extinct reptile, not necessarily belonging to Dinosauria, that existed between about 230 million and 65 million years ago, as well as the stem-mammal Dimetrodon.

Someone or something that is very old or old-fashioned, especially someone who is not willing to change and adapt.

Anything no longer in common use or practice.

a dinosaur

a dinosaur

a dinosaur

dinosaur

Introduced in Volapük Nulik.

Source: wiktionary.org