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 Golf icon is made in Material Design style
developed by Google. This style is based on extremely simplified shapes, thin two-pixel lines, and is optimized for 24x24 px. Unlike other vector icon packs that have merely hundreds of icons, this icon pack contains 5,700 icons, all in the same style and quality.