hy·po·pi·tu·i·ta·rism 
(hī′pō-pĭ-tĭ-tə-rĭz′əm, -ty-)
(hī′pō-pĭ-tĭ-tə-rĭz′əm, -ty-)n.
1. Deficient or diminished production of pituitary hormones.
2. The condition resulting from a deficiency in pituitary hormone, especially growth hormone, characterized by dwarfism in children and sometimes by decreased activity of the thyroid, adrenal, or gonadal glands.
hy′po·pi·tui·tar′y (-tĕr′ē) adj.