/ Dictionary / Index T Thomsen: Meaning and Definition of Find definitions for: Thom•sen Pronunciation: (tom'sun), [key] 1788–1865, Danish archaeologist. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Thompson submachine gun Thomson Related Content Daily Word Quiz: arid Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language