Synonyms of groundless

groundless

adjective

ˈgrau̇n(d)-ləs 

as in unreasonable

having no basis in reason or fact

please stop making groundless accusations against innocent people

fears of a strike proved groundless

Synonyms & Similar Words

• unreasonable
• unfounded
• baseless
• unsubstantiated
• unwarranted
• irrational
• unsupported
• false
• invalid
• unreasoned
• unnecessary
• absurd
• illogical
• misleading
• foundationless
• meaningless
• fallacious
• weak
• specious
• untenable
• inconsistent
• unsound
• nonvalid
• wrong
• implausible
• unconscionable
• misled
• unconvincing
• flimsy
• gratuitous
• stupid
• uncalled-for
• nonsensical
• foolish
• nonlogical
• asinine
• fatuous
• preposterous
• silly
• unwise
• insane
• brainless
• lunatic
• ill-advised
• harebrained
• simpleminded
• mad
• nutty
• senseless
• wacky
• whacky
• crazy
• crackpot
• half-witted

Antonyms & Near Antonyms

• reasonable
• valid
• justified
• good
• hard
• reasoned
• just
• well-founded
• confirmed
• rational
• substantiated
• certified
• logical
• well-grounded
• true
• real
• actual
• informed
• sensible
• wise
• validated
• genuine
• certain
• sane
• sober
• sure
• verified
• corroborated
• plausible
• clear
• credible
• sound
• solid
• compelling
• persuasive
• commonsense
• convincing
• satisfying
• cogent

Example Sentences

Recent Examples of groundless

The bill was first introduced last year as Republicans focused on noncitizen voting Ahead of the 2024 election, Trump and his allies repeated the groundless claim that Democrats planned to cheat by encouraging noncitizens to illegally vote. —Jude Joffe-Block, NPR, 12 Mar. 2025

The claims of an invasion of the Eastern seaboard by swarms of drones has every marker of a groundless social media frenzy. —Michael Hiltzik, Los Angeles Times, 24 Dec. 2024

Yet there’s much more to be said about Ohanian’s original article, as well as the glee with which conservatives seized on its headline claim as the basis for largely groundless attacks on California’s economic policies. —Michael Hiltzik, Los Angeles Times, 3 Dec. 2024

That’s based on the groundless notion that disability is easy to apply for and receive. —Michael Hiltzik, Los Angeles Times, 26 Nov. 2024