A freerunner is a person who moves through the city by running, vaulting walls, jumping gaps, and using stairs, rails, and rooftops as a playground. School-book lines often name the activity; the word freerunner itself is the person. The sport’s name is freerunning.

Though actually, many people mix this up with parkour. Parkour is more about getting from A to B in a direct, efficient way. Freerunning, a later English name from the same street-sport world, often allows extra flips and showy moves, just to move with style. In Taiwan both usually get called 跑酷, so a student may not hear a difference until they watch English videos.

It is a young, city, sports-and-video word, not a formal one. “Free” here is about moving without a set track or a closed gym, not about costing nothing.