abnormal thyroid gland morphology ectopic thyroid gland MP:0013233 MPheno.ontology a thyroid gland located outside of its normal position anterior to the laryngeal cartilages; usually due to abnormal migration of the thyroid diverticulum down from the foramen cecum at the posterior aspect of the tongue to its permanent pre-tracheal location; ectopic thyroid tissue is frequently found along the course of the thyroglossal duct or laterally in the neck, as well as in distant places such as the mediastinum and the subdiaphragmatic organs; the most common ectopic location is near its embryological origin at the foramen caecum, resulting in a lingual thyroid ectopic thyroid thyroid ectopy