1. A very messy or sloppy individual.
2. A word (usually used in the form of a verb) that can be used for just about anything in just about any tense.
1. That kid Justin is a slop. Just look at the way he eats his food.
2a. You tryn to slop me the ketchup.
2b. When I was at work today a slopped $150 in tips.
3c. Guy: You tryn to slop for just 5 seconds?
Girl: I already slopped around with another guy tonite.