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Symbol, Chemistry.


plural Fr. Frs. franc.


plural fr. frs. franc.
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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World English Dictionary
the internet domain name for

abbreviation for
1.  Christianity
 a.  Frater
 b.  Father
the chemical symbol for
2.  francium
[(for sense 1a) Latin: brother]

abbreviation for
Faeroes (international car registration)

abbreviation for

abbreviation for
1.  Christianity Father
2.  France
3.  French
4.  the German equivalent of Mrs
[(sense 4) from German Frau]

Collins English Dictionary - Complete & Unabridged 10th Edition
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American Heritage
Medical Dictionary

The symbol for the element francium.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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American Heritage
Science Dictionary
The symbol for francium.
francium   (frān'sē-əm)  Pronunciation Key 
Symbol Fr
An extremely unstable, radioactive element of the alkali group. It is the heaviest metal of the group. Francium occurs in nature, but less than 28.35 g (1 oz) is present in the Earth's crust at any time. It has approximately 19 isotopes, the most stable of which is Fr 223 with a half-life of 21 minutes. Atomic number 87; valence 1. See Periodic Table.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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Computing Dictionary

fr definition

The country code for France.

The Free On-line Dictionary of Computing, © Denis Howe 2010 http://foldoc.org
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American Heritage
Abbreviations & Acronyms
  1. fraction

  2. French

  1. family room

  2. Federal Register

  3. fire damage

  4. full rate

  1. frame

  2. franc

  3. from

  1. Father

  2. France

  3. Frau

  4. French

  5. Friar

  6. Friday

The American Heritage® Abbreviations Dictionary, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
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Encyclopedia Britannica


heaviest chemical element of Group 1 (also called Group Ia) in the periodic table, the alkali metal group. It exists only in short-lived radioactive forms. Natural francium cannot be isolated in visible, weighable amounts, for only about 30 grams (about 1 ounce) occur at any time in the entire crust of Earth. Marguerite Perey discovered francium (1939) while studying actinium-227, which decays by negative beta decay (electron emission) to an isotope of thorium (thorium-227) and by alpha emission (about 1 percent) into an isotope of francium (francium-223) that was formerly called actinium K (AcK) and is a member of the actinium decay series. Though it is the longest-lived isotope of francium, francium-223 has a half-life of only 21 minutes. Isotopes of francium with masses between 204 and 224 have been artificially prepared, and, because natural francium cannot be concentrated, it is also prepared by neutron irradiation of radium to produce actinium, which decays to produce traces of francium. The chemistry of francium can be studied only by methods designed for trace quantities. In all respects, its observed behaviour, including the oxidation state of +1, is that to be expected of an alkali element filling a place just below cesium in the periodic table of the elements

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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Example sentences for fr
He felt he had never truly been upfront about his past with fr.
The sacraments through the ages produced by ewtn hosted by fr.
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