Wiktionary
n. a firefighter who parachutes into a remote area to combat wildfires.
Wikipedia
A smokejumper is a wildland firefighter who parachutes into a remote area to combat wildfires.
Smokejumpers are most often deployed to fires that are extremely remote. The risks associated with this method of personnel deployment are mitigated by a training program that has developed over more than 70 years. Smokejumpers are capable of reaching a wildfire shortly after ignition, when it is still relatively small and extinguishing the blaze before it becomes a problem to land managers and the public. When there is no significant fire activity, smokejumpers can also be used for outside fire suppression in work assignments such as forestry, disaster relief and emergency management.