This is an image of the profile of a human head facing towards the right. The head has no features on it. In the mouth of the figure is a whistle like shape with a musical note coming out of it.
This Referee 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.