Do you really mean abstract? It seems to me you mean something more like generic. There is nothing 'abstract' about any of these missiles, especially if they hit you at speed. They are all concrete objects.
How about one of these?
missile
projectile
ball (which etymologically refers not to roundness but to being projected through the air) or if you prefer a made up word: ballistile
Yes, I guess I really meant the
class word for such objects. Words like missile and projectile are too broad; manipulandum is better because really, the object does not have to be a projectile, it could be a counter or piece like somebody else suggested. Balls, pucks and shuttlecocks just happen to all be projectiles; my mistake if I stressed that feature. So a word that means, "A manipulandum that is the focus of, or central to, play in a game" is what I'm looking for. Does that make more sense?
