pituitary UK /pɪˈtjuːɪt(ə)ɹi/US /pɪˈtuɪˌtɛɹi/adjective 2noun 2forms 1 adjective2 •Of or relating to the pituitary gland. •Mucous. noun2 •The pituitary gland; sometimes including together with the pituitary stalk. •An extract from the pituitary gland. formspituitaries