Why are fawns called hiders?

Answer 1

It is their best means of protection. They hide whenever they feel threatened because they are too small to run. That is also why they have spots and have the coloring they have, to blend in with fields and forest and long grass.

Answer 2

When a fawn is called a hider, it often has a coat that has spots. These spots cause the deer to be very difficult to see when it is lying on the ground in the leaves and grass.