Dinosaurs

I have always pronounced dinosaur like 'die no source' till recently.
This is because I thought dinosaur's spell was dinosaurs, for singular, not for plural.
Of course I've mispronounced plural dinosaurs as dinosaurs-es (like die-no-sources).

I have an excuse, though.
Many dinosaur's names end with 'saurus', e.g. tyrannosaurus, so I thought a 'dinosaurs' was a name for a 'dinosaur'.

hm...hehe.. it is a terrible excuse. It doesn't make sense!