amorphous shape(n = noun.shape) - an ill-defined or arbitrary shape;
is a kind of form, shape
has particulars: shapelessness, blob, space

amorphous, angular shape, bell shape, change of shape, change shape, concave shape, cone shape, convex shape, curved shape, disk shape, distorted shape, funnel shape, gaussian shape, good shape, in shape, leaf shape, natural shape, out of shape, polygonal shape, poor shape, round shape, shape, shape constancy, shape up, structural shape, take shape, top shape, wave shape, wedge shape