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definitions

tauto-

  1. a combining form meaning “same,” used in the formation of compound words: tautomerism.

Origin of tauto-

< Greek, combining form of tautó, contraction of tò autó the same
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for tauto-

tauto-

before a vowel taut-

combining form
  1. identical or sametautology; tautonym

Word Origin for tauto-

from Greek tauto, from to auto
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
tauto- in Medicine

tauto-

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