Airsoft (not softair, this isnt soviet russia where everything is backwards) is usually considered a hobby, but take it from me, there is a risk for injury and it also gets the adrenaline rushing. So, is it a sport, hobby, or both? Personally, I think it is both.

A sport is typically defined by a competitive aspect, hence competitive sports. However sports are also deemed on an Oxygen intake level that rate the difficulty.
Ok in example...
In highschool your basic sports are rated, however a sport is not always plain to see. According to Oxygen intake reports Cheerleading is the most difficult of high school sports. Followed by football. Now going on this track you would assume to see things like soccer and tennis next. Not to dissapoint but the oxygen intake suggests that competitive Marching Band and Winter competitive Percussion Ensamble are more "difficult".
So the question would require research and questioning before the answer could be attained.

To me its both. Heres my point, to those who think it is a hobby do it in there spare time and cant do it full time like a pro. I play competitive a little when my work buds need a sixth and they play all time so its a sport to them.