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absorbance

or ab·sorb·an·cy

[ab-sawr-buh ns or ab-sawr-buh n-see; -zawr-]
noun Physics.
  1. the capacity of a substance to absorb radiation, expressed as the common logarithm of the reciprocal of the transmittance of the substance.

Origin of absorbance

First recorded in 1945–50; absorb(ent) + -ance
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for absorbance

absorbance

noun
  1. physics a measure of the light-absorbing ability of an object, expressed as the logarithm to base 10 of the reciprocal of the internal transmittanceSee transmittance
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
absorbance in Medicine

absorbance

[əb-zôr′bəns]
n.
  1. In spectrophotometry, equal to 2 minus the log of the percentage transmittance of light.extinction optical density
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.