definition of physical systems in physics
physical system (Noun) The portion of the physical universe chosen for analysis, with everything outside the system known as the environment. Freebase (2.00 / 2 votes) Rate this definition: Physical system. In physics, the word system has a technical meaning, namely, it is the portion of the physical universe chosen for analysis. Everything outside the system is known as the environment, which in analysis is ignored except for its effects on the system.