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Synonyms

untruthful

American  
[uhn-trooth-fuhl] / ʌnˈtruθ fəl /

adjective

  1. not truthful; wanting in veracity; diverging from or contrary to the truth; not corresponding with fact or reality.

untruthful British  
/ ʌnˈtruːθfʊl /

adjective

  1. (of a person) given to lying

  2. diverging from the truth; untrue

"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

Other Word Forms

  • untruthfully adverb
  • untruthfulness noun

Etymology

Origin of untruthful

Middle English word dating back to 1325–75; un- 1, truthful

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Sentencing the three on Tuesday at Southwark Crown Court, Judge Christopher Hehir called Dale a "thoroughly devious and untruthful and manipulative young woman".

From BBC • Jan. 20, 2026

He calls this truth-telling, no matter how untruthful his guests are.

From The Wall Street Journal • Nov. 9, 2025

The part that is so infuriating is how misleading and untruthful it is.

From Los Angeles Times • Nov. 15, 2024

Justice Merchan reminds jurors that if they find just one part of a testimony untruthful, they may disregard the whole testimony of that witness.

From BBC • May 30, 2024

There’s no question that this Texas-of-the- mind fable is often synthetic, sometimes untruthful, and frequently romantic, but that in no way diminishes its strength as a symbol.

From "Travels with Charley in Search of America" by John Steinbeck

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.