goi·ter (goi?t?r)n. A noncancerous enlargement of the thyroid gland, visible as a swelling at the front of the neck, that is often associated with iodine deficiency. Also called struma.[French goitre, back-formation from Old French goitron, throat, gullet, from Vulgar Latin *gutt?ri?, gutt?ri?n-, from Latin guttur.]goi?trous (-tr?s) adj.American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.goi?ter (?g?? t?r) n. an enlargement of the thyroid gland on the front and sides of the neck. Also, esp. Brit.,goi?tre.[1615?25;