Inflicting and sustaining injuries

рассечённая бровь an eyebrow with a gash in it
рассекать/рассечь Nd/(себеd) бровьa to make a cut in N's/one's eyebrow
На левой брови (or брови) был маленький шрам. Это мальчишки в школе рассекли ему бровь камнем. He had a small scar on his left eyebrow. It was from the time the boys at school threw a rock at him and cut open his eyebrow.
Он упал и рассёк себе бровь. He fell and cut his eyebrow.