Type: Term Pronunciation: thī′rō-lib′ĕr-in Definitions: 1. A tripeptide hormone from the hypothalamus, which stimulates the anterior lobe of the hypophysis to release thyrotropin; l-pyroglutamyl-l-histidyl-l-prolinamide. Synonyms: thyroid-stimulating hormone-releasing factor, thyrotropin-releasing hormone Found on http://www.medilexicon.com/medicaldictionary.php?t=92005