A thermodynamic process where no heat is exchanged with the surroundings is

An adiabatic process is defined as a thermodynamic process in which no heat exchange occurs between a system and its surroundings [2]. In such a process, the heat transfer (Q) is zero, meaning heat neither enters nor leaves the system [3]. Consequently, any change in the internal energy of the system is solely due to work done by or on the system. This differs from an isothermal process, where the temperature remains constant [3], and an isobaric process, where the pressure remains constant [2]. In adiabatic changes, temperature fluctuations are internal and result from changes in pressure or volume rather than external heat flow [2]. For instance, when an air parcel rises and expands without heat exchange, it undergoes adiabatic cooling [4]. Isotropic, meanwhile, refers to uniformity in all directions rather than a specific heat-related thermodynamic process.

Sources

1. [1] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 22: Vertical Distribution of Temperature > 22.3. Adiabatic Lapse Rate (ALR) > p. 296
2. [2] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 22: Vertical Distribution of Temperature > A Parcel of Rising Air > p. 297
3. [3] https://www.sciencedirect.com/topics/engineering/adiabatic-process
4. [4] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 24: Hydrological Cycle (Water Cycle) > Adiabatic Temperature Changes > p. 330