/ Dictionary / Index T transmethylation: Meaning and Definition of Find definitions for: trans•meth•yl•a•tion Pronunciation: (trans"meth-u-lā'shun, tranz"-), [key] — n. Chem. the transfer of a methyl group from one compound to another. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. transmembrane transmigrant Related Content Daily Word Quiz: placid Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language