The traditional definition of a rugged notebook is one that can take some limited amount of water, it is designed to for repeated drops onto a hard surface, the ports are sealed to prevent dust and other contaminates from entering the system. So, you might image a Panasonic Toughbook.
By that definition a MacBook Pro isn't rugged at all. Its designed to last for years, not in a desert or a police car, but on a desk or in a padded bag that provides basic protection to the laptop. There is no sealing against water, dust or anything else.
They ARE made with tremendous quality so IF they are taken care of reasonably well they tend to last for YEARS. But, rugged? Not really.