Definition of what you understand by the name diversity?

Diversity is the same as variety. All things that have unity,identity. A thing that has an unique form has no diversity. Diversity of meanings on a Word, for instance. Diversity of symptoms in a particular disease, while in others you may find an unique symptom. So, this unique sympton characterize the disease for itself which applies an identity on it, because you needn't to search for another symptoms. It tells you all because the disease has an identity. But these features are applied to many other things in life, such as environment, and others.