n. a dopamine-receptor agonist used to relieve the symptoms of Parkinson’s disease and, due to its ability to inhibit release of the pituitary hormone prolactin, to treat galactorrhea. It is also used to treat amenorrhea, infertility, prolactin-secreting adenomas, and parkinsonism, including the extrapyramidal symptoms induced by conventional antipsychotic agents. U.S. trade name: Parlodel.