having the shape of a trapezoid, a quadrilateral with one pair of parallel sides

台形の, 台形状の
having the form of a ring

環状の, 輪形の
having a series of sharp, pointed projections along the edge

鋸歯状の (こがたはじょうの), 鋸のような (のこぎりのような)
resembling a slanted or tilted rectangle

ひし形の, 台形の
having the shape or characteristics of an octagon, which is a polygon with eight sides and eight angles

八角形の, 八角の
characterized by or resembling a tetrahedron, which has four triangular faces

四面体の, テトラヘドロンの
having the shape of a pentagon, which is characterized by five straight sides and five angles

五角形の, ペンタゴナルな
having the form or characteristics of a cone, which is a three-dimensional geometric shape with a circular base tapering to a point at the apex

円錐形の, コーン型の
having a spiral or wound shape, often forming a series of loops or turns

螺旋状の (らせんじょうの), 巻いた (まいた)
resembling a structure with a polygonal base and triangular sides, often tapering to a point at the apex

ピラミッド型の, ピラミッドのような
