Frontside
Also known as: FS
Direction of a trick or turn where the skater's chest faces the obstacle or the outside of the curve.
Extended definition
It's one of the two concepts that organise half of skating's vocabulary. In a frontside grind or slide you enter with your chest facing the rail or ledge; in transition, frontside is turning while seeing the outside of the ramp. It feels very different from its backside version and almost every trick has both. Sorting out frontside vs backside is one of the first things to get clear to follow any tutorial.
Origin / etymology
From surfing: the turn where the surfer faces the wave.