(1) Obsolete term for gonadotropin-releasing hormone. SYN: gonadotropin-releasing factor. (2) A decapeptide from pig hypothalami that induces release of both lutropin and follitropin in constant proportions and thus acts as both luliberin and folliberin. SYN: luteinizing hormone/follicle-stimulating hormone-releasing factor. Cf.: gonadotropin-releasing hormone [gonad + L. libero, to free, + -in]