- - anterior p. of left medial segment IV of liver [TA] the part of the medial segment of the liver that includes the quadrate lobe. SYN: quadrate part of liver [TA], pars quadrata hepatis.- mesenteric p. of small intestine the freely movable p. of the small intestine supplied with a mesentery, comprising the jejunum and ileum. SYN: intestinum tenue mesenteriale.- subcutaneous p. of external anal sphincter SYN: subcutaneous part of external anal sphincter. See external anal sphincter.
* * *por·tion (porґshən) a part or division of a larger structure; called also portio [TA], part, and pars.
Medical dictionary. 2011.