Im no expert on this stuff but doesnt the name dinosaur comes from the Greek words deinos (“terrible” or “fearfully great”) and sauros (“reptile” or “lizard”) and is a common name given to a group of reptiles, often very large, that first appeared in the Late Triassic Period about 215 million years ago and thrived worldwide for some 150 million years. Most died out by the end of the Cretaceous Period, about 65 million years ago, but many lines of evidence now show that one lineage evolved into birds about 150 million years ago?