nounInanatomy, a rhomboideus. nounInanthropology, a cranium the norma verticalis of which has a rhomboid form. from the GNU version of the Collaborative International Dictionary of English. noun(Geom.)An oblique
rhomboidal: Specifically, in anatomy, said of muscles whose fibers run obliquely from the point of origin to the point of insertion, as in the so-called ‘penniform muscles’ in which a large number of fibers are attached to a long tendon-like b