/ Thesaurus / T Synonyms of thyroxin Find synonyms for: Noun1. thyroxine, thyroxin, tetraiodothyronine, T, thyroid hormoneusage: hormone produced by the thyroid glands to regulate metabolism by controlling the rate of oxidation in cells; "thyroxine is 65% iodine"WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: magnanimous Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language