Adiabatic Process

Adiabatic process is a thermodynamic process in which there is no heat exchange with the surroundings.  The system undergos the process of neither gains nor loses of heat to its surroundings.  The term "adiabatic" comes from the Greek words "a," meaning "without," and "diabatos," meaning "passage."

During an adiabatic process, the energy transfer occurs only as work done on or by the system.  The internal energy of the system changes due to the work done on or by the system, but there is no transfer of heat across the boundaries of the system.