The term 'Absence of Motion' can be described by two crossword solutions: REST (4 letters) and INERTIA (7 letters). REST is a state of inactivity, where no physical movement is taking place. INERTIA is the resistance of any physical object to any change in its state of motion or REST. It is the tendency of an object to remain at REST or in motion unless acted upon by an external force. Both terms refer to the lack of motion, which is the absence of motion.