pituitary gland: Meaning and Definition of

pitu'itary gland"

1. a small, somewhat cherry-shaped double structure attached by a stalk to the base of the brain and constituting the master endocrine gland affecting all hormonal functions in the body, consisting of an anterior regionorthat develops embryonically from the roof of the mouth and that secretes growth hormone, LH, FSH, ACTH, TSH, and MSH, a posterior regionorthat develops from the back of the forebrain and that secretes the hormones vasopressin and oxytocin, and an intermediate partderived from the anterior region but joined to the posterior region, that secretes the hormone MSH in lower vertebrates. Also calledSee diag. under