/ Dictionary / Index M methyltheobromine: Meaning and Definition of Find definitions for: meth•yl•the•o•bro•mine Pronunciation: (meth'ul-thē"u-brō'mēn, -min, meth"-), [key] — n. Chem. caffeine. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. methyltestosterone methylthionine chloride Related Content Daily Word Quiz: perspicacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language