Talk:Rhomboid major muscle
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[edit] Rhomboid major muscle is not "diamond-shaped"
A rhombus is a parallelogram (which has parallel and equal opposite sides) with 4 equal sides; a rhomboid is a parallelogram with unequal adjacent sides (i.e., not a rhombus) and oblique angles (i.e., not a rectangle).
Most equate being diamond-shaped with being a rhombus, in which case the article is in a sense saying that the word rhomboid suggests a rhombus, which is like saying the word humanoid suggests a human. In a sense it does suggest, or bring to mind, a human, but with the connotation (if not definition) that, while like a human, it is also not a human. Similarly for rhomboid, and I think all -oids. Even if you don't equate being diamond-shaped with being a rhombus (some regard some kites as being diamond-shaped as well), a rhomboid should/would not be considered diamond-shaped because it lacks the equal adjacent sides (by definition) and bilateral symmetry necessary for the latter. For a less "definitive" approach, if you just look at the diagram of the Rhomboideus muscles, there is no way to make them into a diamond-shape, the oblique unattached borders of the muscles being markedly longer than their respectively adjacent attached vertical borders. I propose the following explanation for its name (perhaps it can be simplified):
"The Rhomboideus muscles (major and minor) are named for their geometrical shape. In geometry, a rhomboid is a parallelogram (with opposite sides parallel and equal in length) that has unequal adjacent sides forming oblique, non-rectangular angles. The Rhomboideus muscles each have two vertical borders attached to the spinal column and medial border of the scapula respectively (with the spinal attachment superior to the scapular) that are equal in length to each other and shorter than the two unattached borders, the latter also parallel and equal in length to each other, and angled obliquely downward laterally."Jauntymcd 14:42, 20 March 2007 (UTC)
