It's and outline of a person. They are in the middle of swinging a golf club. The club is over their left shoulder and has two lines coming off of it indicating that it is moving fast.
This is a Golf icon. We've made it in iOS style
, first introduced in iOS version 7 and supported in all later releases up until now (at least iOS 11). This style is based on thin two-pixel lines and is optimized for 50x50 px. Unlike other vector icon packs that have merely hundreds of icons, this icon pack contains 13,300 icons, all in the same style and quality.