part of part of in taxon results in development of diencephalon development pituitary gland development GO:0021983 hypophysis development The progression of the pituitary gland over time from its initial formation until its mature state. The pituitary gland is an endocrine gland that secretes hormones that regulate many other glands. endocrine system development gland development anatomical structure development Vertebrata <vertebrates> pituitary gland