Meaning of ancestral property

In my opinion they are such properties which are not self earned properties of your father or Grand Father. Hindu Undivided Family properties assume the status if even selt earned properties are thrown onto the hotch-potch

Defination is very simple.

Property which is not acquired by you

or 

Property acquired by your father or father's father or father's father's father is ancestral property for you

how does father's self acquired property comes under ancestral property?

i mean self earned properties,acquire can have a different meaning which can be both inherited,bought,purchase...please be specific