Simple Definition of fallacious
: containing a mistake : not true or accurate
Examples of fallacious in a sentence
<it's fallacious to say that something must exist because science hasn't proven its nonexistence>
<consumers who harbor the fallacious belief that credit-card spending will never catch up with them>
Did You Know?
Oh what a tangled web we weave / When first we practise to deceive! So wrote Sir Walter Scott in his 1808 poem Marmion. Scott’s line wasn't written with etymology in mind, but it might be applied to the history of "fallacious." That word traces back to the Latin verb fallere ("to deceive"), but it passed through a tangle of Latin and French forms before it eventually made its way into English in the early 1500s. Other descendants of "fallere" in English include "fail," "false," and "fault."
First Known Use of fallacious
Seen and Heard
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