Smoke
Ignore-Amus
Alternatively I sometimes like to not consider a tree a bonsai until it reaches a state upon which I would be comfortable to enter it into a show without embarrassment, I kinda like that definition too.
There is no other definition. The easiest definition for bonsai "I" tell people (this is not definitive mind you) is that after you have trained some branches with wire and removed it. Rewired the tree and then removed it again, you have reached a place that could be called bonsai. Depending on your creative, talent and technique, it may still look like shit, but at least it has met some criteria of what makes a plant a bonsai.
If after two wiring sessions you still have a plant that looks like shit, maybe stamp collecting is a way to go.....