The physical aspects of a phenomenon or a system, especially those studied scientifically.
Newtonian physics was extended by Einstein to explain the effects of travelling near the speed of light; quantum physics extends it to account for the behaviour of atoms.
The branch of science concerned with the study of the properties and interactions of space, time, matter and energy.
The natural constitution, or physical structure, of a person.
The trained muscular structure of a person's body.