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Synonyms

baseless

American  
[beys-lis] / ˈbeɪs lɪs /

adjective

  1. having no base; without foundation; groundless.

    a baseless claim.


baseless British  
/ ˈbeɪslɪs /

adjective

  1. not based on fact; unfounded

    a baseless supposition

"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

Etymology

Origin of baseless

First recorded in 1600–10; base 1 + -less

Explanation

If something's baseless, it can't be proven or justified. A baseless accusation of cheating, for example, has no facts or evidence to back it up. Baseless facts in a research paper don't have sources — they may have simply come from the writer's own imagination. A baseless allegation is when one person accuses another of doing something wrong, without having any solid proof or reason for the accusation. The sense of base that baseless comes from is "foundation," from the Greek basis, "step or pedestal."

Keep Reading on Vocabulary.com

Vocabulary lists containing baseless

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.

Baseless and ill-informed outrage for the purposes of personal social media traction serves no one - least of all the injured player.

From BBC • May 13, 2025

Baseless rumors ricocheted through social media alleging that the federal government was attempting to lure demonstrators to Washington to arrest them.

From Washington Post • Sep. 18, 2021

Baker’s title alludes to an early-1950s Air Force project, Project Baseless, that pushed for “combat capability in biological and chemical warfare at the earliest possible date.”

From Seattle Times • Jul. 31, 2020

Baseless accusations should not be allowed to ruin people’s lives.

From Washington Times • Feb. 14, 2018

Baseless apprehensions of the return of the treacherous Pagan and his profligate employer, with the return of their victim—despairing convictions of his own helplessness and infirmity rose startlingly in his mind.

From Antonina by Collins, Wilkie