WordNet
n. the posterior lobe of the pituitary body; primarily glandular in nature [syn: posterior pituitary gland, neurohypophysis, pars nervosa]
Wikipedia
The posterior pituitary (or neurohypophysis) is the posterior lobe of the pituitary gland which is part of the endocrine system. The posterior pituitary is not glandular as is the anterior pituitary. Instead, it is largely a collection of axonal projections from the hypothalamus that terminate behind the anterior pituitary which serves as a site for the secretion of neurohypophysial hormones ( oxytocin and vasopressin) directly into the blood. The hypothalamic–neurohypophyseal system is composed of the hypothalamus (the paraventricular nucleus and supraoptic nucleus), posterior pituitary, and these axonal projections.