adiabatic process occurs without heat transfer with its surrounding.In isentropic process entropy remains constant,it is known as reversible adiabatic process. adiabatic process occurs without heat transfer with its surrounding.In isentropic process entropy remains constant,it is known as reversible adiabatic process.

Can a process be reversible and non adiabatic?

As long as the work is reversible (δW=−PdV), the process can be called reversible. For a reversible process, you have δQ=TdS but this is not a property of the heat exchange, only a consequence of the fact the entropy is increased by the heat only (no extra growth by some irreversible work).

Which relation is correct for adiabatic reversible process?

PΔV=0.