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definitions

spectro-

  1. a combining form representing spectrum in compound words: spectrometer.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for spectro-

spectro-

combining form
  1. indicating a spectrumspectrogram
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
Word Origin and History for spectro-

word-forming element meaning "of or by a spectroscope," also "of radiant energy," from comb. form of spectrum.

Online Etymology Dictionary, © 2010 Douglas Harper
spectro- in Medicine

spectro-

pref.
  1. Spectrum:spectroscope.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.