Hyperplasia means increase in the cell number.
It tends to occur only in organs where the cells retain the ability to divide. It can be physiologic or pathologic.
The morphology of the organ on gross or the cells on microscopy does not differ in physiologic or pathologic hyperplasia. What differentiates the two is the inciting stimulus.
for eg- Breast/ Endometrial hyperplasia is a feature of pregnancy as well as in certain hormone producing tumors of the ovary. The tissue microscopically, only shows increased number of mature cells. However, the hyperplasia that occurs due to pregnancy (physiologic) process is labelled as "Physiologic" while that which occurs due to ANY pathologic process is labelled as
"Pathologic" hyperplasia.