Top two short strokes splay outward — an abstract marker of dividing or splitting, also seen on 兰, 关, 单. Sits over the ox 牛 below to picture a carcass being cleaved: the act of halving. Indexed under Kangxi #24 十 by tradition, though no ten-radical is visibly present.
Body of the character is an ox — pictograph of horns rising from a head. Below the splitting strokes above, the picture is unmistakable: cleaving an ox down the middle, the original ritual of dividing a sacrificial animal between two parties. From that ancient butcher's image came the modern meaning 'half'.
Filed under radical 十 (shí, #24) by convention. 十 is not a separate component in 半, so no strokes are highlighted.
