molecular weight
noun Chemistry.
the average weight of a molecule of an element or compound measured in units once based on the weight of one hydrogen atom taken as the standard or on 1/16 (0.0625) the weight of an oxygen atom, but after 1961 based on 1/12 (0.083) the weight of the carbon-12 atom; the sum of the atomic weights of all the atoms in a molecule. Abbreviation: mol. wt.
Nearby words
molecular rotation, molecular sieve, molecular spectrum, molecular surgery, molecular volume, molecular weight, molecularity, molecule, molehill, moleskin, moleskins
Origin of molecular weight
First recorded in 1875–80
Also called formula weight.
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British Dictionary definitions for molecular weight
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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Medicine definitions for molecular weight
molecular weight
n.
The sum of the atomic weights of all the atoms in a molecule.formula weight
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Science definitions for molecular weight
molecular weight
The sum of the atomic weights of the atoms contained in a molecule. Also called relative molecular mass
The American Heritage® Science Dictionary
Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Culture definitions for molecular weight
The New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.