x1 is a block [3-dimensional shape/form] of material x2, surfaces/sides x3.
x3 sides/surfaces should include number, size, and shape; also polyhedron (= pitybli having flat/planar sides/surfaces). regular polyhedron (= kubybli, blikubli), brick (= kitybli); See also tapla, kubli, tanbo, canlu, kojna, sefta, bolci, kurfa, tarmi.