| Noun | 1. | prolactin - gonadotropic hormone secreted by the anterior pituitary; in females it stimulates growth of the mammary glands and lactation after parturition gonadotrophic hormone, gonadotrophin, gonadotropic hormone, gonadotropin - hormone secreted by the anterior pituitary gland and placenta; stimulates the gonads and controls reproductive activity lactogen - any agent that enhances milk production |