When they say "lot" they are most likely referring to selecting "Need", "Greed" or "Pass" when to comes to allotting loot to individuals. In some MMOs it is referred to as "rolling".

Though it is possible that someone is misspelling "loot".

So you can go ahead and continue to call "lotting" "rolling" just as another person can refer to it as "lot".

You can also call your bounty from the dungeons/quests/hunts/what-have-you as "loot" as another can call it "booty", "treasure" or whatever their hearts desire. Whatever blows your fur back.