1. Something a semi is hauling thats bigger than the trailer.
2. Someone who is really fat and needs to drop about 300 pounds by actually walking instead of riding their damn motorized wheelchair around wal-mart all day.
This term is usually given to an extremely fat person e.g. someone so fat that they have fat deposits on their back and an arse so big/wide that it’s in a different time zone to the rest of the body.
“Dave, mate, your bird is one ‘ell of a WIDE LOAD!” {Make air hornsound} “Coming through!”