go·se·rel·in 
(gō′sə-rĕlĭn)
(gō′sə-rĕlĭn)n.
A synthetic peptide analog of gonadotropin-releasing hormone used to treat prostate cancer, endometriosis, and advanced breast cancer.
[Blend of gonadorelin (from GONADO(TROPIN-)REL(EASING HORMONE) + -IN) and SERINE.]