mendacious

men-DAY-shuss /menˈdeɪ.ʃəs/
adjectiveC2GRESAT
formalliterary

Not telling the truth; habitually lying or containing falsehoods.

A formal, high-register term for lying or untruthful statements.

The story behind the word. Latin mendax referred to someone with a moral defect or fault in speech. It shares a deep Indo-European root with 'amend' (to fix a defect). A mendacious person speaks with deliberate flaws in the truth.

Word relationships

  • untruthful: Untruthful is standard English, whereas mendacious carries formal weight and often implies habitual lying.
  • deceitful: Deceitful emphasizes the intent to trick, while mendacious emphasizes the falsehood of the statements.
  • truthful: Truthful means telling or expressing the truth.
  • veracious: Veracious is a formal term meaning habitually truthful.

Commonly confused with

  • mercenary: Mercenary means motivated solely by money, while mendacious means dishonest or lying.

Word family

  • mendacity (noun): Untruthfulness; a tendency to lie.
  • mendaciously (adverb): In a lying or dishonest manner.

Collocations

  • mendacious claim
  • mendacious report
  • mendacious statement

Idioms & expressions

  • economical with the truth
  • lying through one's teeth

Example sentences

  • "The executive was forced to resign after a series of mendacious statements regarding corporate revenue were uncovered." Political scandal

Memory hook

MEN-DAY-shuss: MEN telling lies all DAY long. Habitually untruthful.

When not to use

Avoid in casual conversation where 'lying' or 'untruthful' sounds more natural.

Fun facts

  • Winston Churchill famously avoided calling opponents 'liars' in Parliament by calling their claims 'mendacious assertions'.

Explore more words

perfidy, veracity, traduce, malicious

LangBlitz
Take your vocabulary further with LangBlitz

Our English vocabulary app: FSRS spaced repetition, 5,000+ curated words across 119 topic groups, CEFR A1 to C2. Explore your mastery with the beautiful Vocabulary World feature.