basejumping

BASE jumping, also sometimes written as base jumping or basejumping, is an activity that employs a parachute (or a wingsuit and parachute) to jump from fixed objects, with the parachute unopened at the time of the jump. "BASE" is an acronym that stands for the four categories of fixed objects from which one can jump:

* Building
* Antenna
* Span
* Earth

If your parachute is open when you jump, it's not basejumping - that's paragliding.