Definition - What does Absolute Zero mean?
Absolute Zero is the scale of thermodynamic temperature when in lower limit. It is a phase at which entropy and enthalpy of the cooled ideal gas come at the maximum value that is 0. It is a temperature where all motions in matter stop and are considered unreachable. Temperature of any object thus, depends upon how fast molecules and atoms are oscillating. At Absolute Zero, the oscillations are at the slowest they can possibly be.
Petropedia explains Absolute Zero
Absolute Zero is commonly considered as the lowest possible temperature. But it is not really lowest enthalpy possible state as all real substances start to depart from ideal gas when it is cooled to change from gas to liquid and then to solid state. On addition of enthalpy of vaporization and fusion, the ideal gas change exceeds in the enthalpy to Absolute Zero. The concept of it to be a limiting temperature consists of many thermodynamic consequences. For instance, all the motion of molecules do not break off at Absolute Zero, but none is present to transfer it to other systems and therefore, it is correct to consider that there is minimal energy at Absolute Zero.