[ tom-suhn ]


  1. Elihu, 1853–1937, U.S. inventor, born in England.
  2. Sir George Paget, 1892–1975, English physicist (son of Sir Joseph John): Nobel Prize 1937.
  3. James, 1700–48, English poet, born in Scotland.
  4. James B.V., 1834–82, English poet.
  5. John Arthur, 1861–1933, Scottish scientist and author.
  6. Sir Joseph John, 1856–1940, English physicist: Nobel Prize 1906.
  7. Virgil, 1896–1989, U.S. composer and music critic.
  8. Sir William. Kelvin, 1st Baron.


/ ˈtɒmsən /


  1. ThomsonSir George Paget18921975MBritishSCIENCE: physicist Sir George Paget, son of Joseph John Thomson. 1892–1975, British physicist, who discovered (1927) the diffraction of electrons by crystals: shared the Nobel prize for physics 1937
  2. ThomsonJames17001748MScottishWRITING: poet James. 1700–48, Scottish poet. He anticipated the romantics' feeling for nature in The Seasons (1726–30)
  3. ThomsonJames18341882MScottishWRITING: poet James, pen name B.V. 1834–82, British poet, born in Scotland, noted esp for The City of Dreadful Night (1874), reflecting man's isolation and despair
  4. ThomsonSir Joseph John18561940MBritishSCIENCE: physicist Sir Joseph John. 1856–1940, British physicist. He discovered the electron (1897) and his work on the nature of positive rays led to the discovery of isotopes: Nobel prize for physics 1906
  5. ThomsonRoy18941976MBritishCanadianWRITING: newspaper proprietor Roy, 1st Baron Thomson of Fleet. 1894–1976, British newspaper proprietor, born in Canada
  6. ThomsonVirgil18961989MUSMUSIC: composerMUSIC: criticMUSIC: conductor Virgil. 1896–1989, US composer, music critic, and conductor, whose works include two operas, Four Saints in Three Acts (1928) and The Mother of Us All (1947), piano sonatas, a cello concerto, songs, and film music
  7. Sir William. See (1st Baron) Kelvin
“Collins English Dictionary — Complete & Unabridged” 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012


/ tŏmsən /

  1. British physicist who discovered the electron in 1897. While experimenting with cathode rays, he deduced that the particles he observed were smaller than an atom. Thomson also made noteworthy studies of the conduction of electricity through gases. He was awarded the Nobel Prize for physics in 1906.

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Nowadays we take for granted the existence of electrons, but this was not true just over 100 years ago, when the atom was thought to be a single unit that had no parts. The breakthroughs came in the late 1890s, when the British physicist J. J. Thomson was studying what we now call cathode-ray tubes. As an electric current passed from the cathode at one end of the tube to the anode at the other, raylike emanations were seen to proceed from the cathode to the anode. Thomson examined the nature of the rays' charge by bringing a positively charged and a negatively charged plate near the path of the rays, and observed that the rays were deflected toward the positive plate, suggesting they had negative charge. A series of experiments in which various objects were placed in the path of the rays showed that they also had momentum (they would cause a small paddle wheel to turn, for example). If they had momentum, that meant (in the physics of the time) that they had mass, suggesting that the rays were composed of tiny particles. Other experimental results, some by other scientists, suggested that the ratio of the charge to the mass of these particles had to be less than one-thousandth the ratio for charged hydrogen atoms. By examining both the energy of the rays and the amount by which an electric charge deflected them, Thomson was able to calculate that these particles had one two-thousandth the mass of a hydrogen atom. The particles, first named corpuscles, were later called electrons. (The term electron was not completely new; it had been invented in 1891 for the rays themselves.) Thomson was thus the first to discover that particles smaller than atoms existed, and for his pioneering work he was awarded the 1906 Nobel Prize for physics.
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Example Sentences

Thomson and Potts were similarly committed to their work in the House office.

From Time

If, on the other hand, you know Thomson’s books about movies — he has published more than 25, including multiple editions of his “Biographical Dictionary of Film” — you will predict, correctly, that “A Light in the Dark” is none of these things.

It reads, at times, like a love letter to the art that has moved Thomson most.

An attorney for Thomson did not immediately respond to a request for comment.

But writing this summer for Thomson Reuters he maintained that at least for the families “there are no good choices.”

Thomson is one of those gifted writers who make any subject that they choose to pick up lively and instructive.

As the critic David Thomson once wrote, "Arnold is beyond reality, beyond bodies even—and he knows it."

“Kevin Costner can be very uninteresting,” concluded David Thomson in his New Biographical Dictionary of Film.

“A man like Costner would be killed by humor,” Thomson once wrote.

Accordingly I cried and waved on Mr. Rankeillor, who came up alone and was presented to my friend Mr. Thomson.

“And that is more than I could look for, Mr. Thomson,” said Rankeillor heartily.

Thirty years before Rousseau, Thomson had forestalled all the sentiments of Rousseau, almost in the same style.

James Thomson, in his Seasons, is the first great nature painter amongst the poets.

Thomson,name under which Nelson speaks of himself in his correspondence with Lady Hamilton, ii.





ThomsenThomson effect