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n. Abbr. rd
A unit expressing the rate of decay of radioactive material, equal to one million disintegrations per second, or one million becquerels.

[After Ernest Rutherford.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


1. (Biography) Ernest, 1st Baron. 1871–1937, British physicist, born in New Zealand, who discovered the atomic nucleus (1909). Nobel prize for chemistry 1908
2. (Biography) Dame Margaret. 1892–1972, British stage and screen actress. Her films include Passport to Pimlico (1949), Murder She Said (1962), and The VIPs (1963)
3. (Biography) Mark, original name William Hale White. 1831–1913, British novelist and writer, whose work deals with his religious uncertainties: best known for The Autobiography of Mark Rutherford (1881) and the novel The Revolution in Tanner's Lane (1887)


(Units) a unit of activity equal to the quantity of a radioactive nuclide required to produce one million disintegrations per second. Abbreviation: rd
[C20: named after Ernest Rutherford]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈrʌð ər fərd, ˈrʌθ-)

1. Daniel, 1749–1819, Scottish physician and chemist.
2. Ernest (1st Baron Rutherford of Nelson), 1871–1937, English physicist, born in New Zealand: Nobel prize for chemistry 1908.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.rutherford - a unit strength of a radioactive source equal to one million disintegrations per second
radioactivity unit - a measure of radioactivity
2.Rutherford - British chemist who isolated nitrogen (1749-1819)
3.Rutherford - British physicist (born in New Zealand) who discovered the atomic nucleus and proposed a nuclear model of the atom (1871-1937)Rutherford - British physicist (born in New Zealand) who discovered the atomic nucleus and proposed a nuclear model of the atom (1871-1937)
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in classic literature ?
At this, night after night, sometimes far into the morning, Rutherford Maxwell would sit and write stories.
Rutherford Maxwell was an Englishman, and the younger son of an Englishman; and his lot was the lot of the younger sons all the world over.
Long after he had gone to bed, Rutherford would hear footsteps passing his door and the sound of voices in the passage.
June came, and July, making an oven of New York, bringing close, scorching days and nights when the pen seemed made of lead; and still Rutherford worked on, sipping ice-water, in his shirt-sleeves, and filling the sheets of paper slowly, but with a dogged persistence which the weather could not kill.
'I'm afraid I haven't,' said Rutherford, apologetically.
The intellectual pressure of the conversation was beginning to be a little too much for Rutherford. Combined with the heat of the night it made his head swim.
Rutherford clutched a chair with one hand, and his forehead with the other.
Rutherford looked at the girl in the doorway with interest.
At the door she paused, and inspected Rutherford with a grave stare.
Rutherford sat down and dabbed his forehead with his handkerchief, feeling a little weak.
She no longer wore the picture-hat, and Rutherford, looking at her, came to the conclusion that the change was an improvement.
Alice Rutherford for scarce a three months, and it was the thought of taking this fair young girl into the dangers and isolation of tropical Africa that appalled him.