(a)  “Park” means, when prohibited, the standing of a vehicle, whether occupied or not, otherwise than temporarily for the purpose of and while actually engaged in loading or unloading.

(b)  “Stop” means, when required, a complete cessation from movement.

(c)  “Stop, stopping or standing” means, when prohibited, any stopping or standing of a vehicle whether occupied or not, except when necessary to avoid conflict with other traffic or in compliance with the directions of a police officer or traffic control sign or signal.