1. When you miss hitting the nail with the hammer and end up hitting a finger and leaving a bloody mess.
2. When you seriously injure yourself.
1. "I was hanging a picture the other day, and fumblehammered my thumb. Before this game, I would have just swore. This time I yelled OUENDAAAAN!!! I think it helped more."
2. One day I fumblehammered my nuts on my bike after I jumped over a ramp.
by Siril Frein February 10, 2006
Get the fumblehammer mug.