[ taw-tol-uh-jee ]
/ tɔˈtɒl ə dʒi /

noun, plural tau·tol·o·gies.

needless repetition of an idea, especially in words other than those of the immediate context, without imparting additional force or clearness, as in “widow woman.”
an instance of such repetition.
  1. a compound propositional form all of whose instances are true, as “A or not A.”
  2. an instance of such a form, as “This candidate will win or will not win.”

Origin of tautology

1570–80; < Late Latin tautologia < Greek tautología. See tauto-, -logy



redundancy tautology
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Examples from the Web for tautologous

  • And the tautologous, useless nature of the hypothesis in the second forces the theory back to the first view.

    Creative Intelligence|John Dewey, Addison W. Moore, Harold Chapman Brown, George H. Mead, Boyd H. Bode, Henry Waldgrave, Stuart James, Hayden Tufts, Horace M. Kallen
  • The phrase pre-established harmony is, strictly speaking, tautologous.

British Dictionary definitions for tautologous

/ (tɔːˈtɒlədʒɪ) /

noun plural -gies

the use of words that merely repeat elements of the meaning already conveyed, as in the sentence Will these supplies be adequate enough? in place of Will these supplies be adequate?
logic a statement that is always true, esp a truth-functional expression that takes the value true for all combinations of values of its components, as in either the sun is out or the sun is not outCompare inconsistency (def. 3), contingency (def. 5)

Derived forms of tautology

tautological (ˌtɔːtəˈlɒdʒɪkəl), tautologic or tautologous, adjectivetautologically or tautologously, adverb

Word Origin for tautology

C16: from Late Latin tautologia, from Greek, from tautologos
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