Probably be a few answers to this but its a mix of ground beef with seasoning, fried and served usually on bread. http://www.astray.com/recipes/?show=Sloppy%20joe%20%232 for 30 ways to fo it if you have to, inc. pizza topping -thats where the Pizza Express 'Sloppy Guiseppe' name comes from - or casserole, potato topping and son. Everyone has a variant on it.
Used to be a big baggy jumper, probably an American expression from the 1950s. As you have asked the question under Food & Drink you may have something else in mind.
Mmmm, my mom makes the best Sloppy Joes! You can buy them pre-made ("Manwich"), but they're nowhere near as good. A Sloppy Joe is basically ground beef broken up and cooked loosely (not in a patty like a hamburger). Ketchup and seasonings are added to make a sauce. The resulting mixture is quite liquid-y
Oops, I hit something with my pinky finger by mistake and my answer posted too soon. Anyway, the resulting mixture is very liquid and somewhat messy, and is scooped onto a hamburger bun (not sliced bread!). Usually served with potato chips (crisps) on the side, and a dill pickle.
Ouisch, LOL! I have family in New Jersey and I had NEVER heard of that sandwich being called a sloppy joe until someone else told me about it! How funny!