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."
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
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'fallacious.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.