NCIt definition : One of the extraoculomotor muscles, which arises from a common tendinous ring in the
posterior portion of the orbit, inserts on the anterior globe, is innervated by CN
III, and functions to depress and adduct the eye.;
Alternative definition : CDISC: A muscle of the eye, in general extending from the annulus of Zinn to the ventral
aspect of the eye at the annulus tendineus; primary function is depression of the
eyeball.;