An intensely large, overbearing, and excessive amount of something. This may be something dreaded, considering that the word 'hell' is embedded in the word itself. Similar to crapload, shitload, motherload, etc. A load from hell.
Oh man, I have a hellload of Spanish homework to do tonight...looks like I'm going to be pulling an all-nighter. T_T
This is a hellload of food, I knew I should've just gotten a happy-meal.
You had better wash that hellload of dirty laundry!