unfounded

adjective

un·​found·​ed ˌən-ˈfau̇n-dəd 

: lacking a sound basis : groundless, unwarranted

an unfounded accusation

Synonyms of unfounded

• unreasonable
• baseless
• groundless
• unsubstantiated

Examples of unfounded in a Sentence

the accusation proved to be unfounded

Recent Examples on the Web

But in the months since, Owens has pushed conspiracy theories about his murder and made unfounded fraud allegations about the finances at Turning Point, which Erika Kirk now runs. —CBS News, 11 Dec. 2025

Lindell -- who has been one of the leading proponents of unfounded claims that voting machines created fraud in the 2020 election -- previously registered a candidate campaign committee with the Minnesota Campaign Finance Board, according to a filing with the board. —Olivia Rubin, ABC News, 11 Dec. 2025

For various unfair and unfounded reasons, many scholars have characterized Bianchi as an always unreliable source. —Via Chronicle Books, Literary Hub, 11 Dec. 2025

Chinese fears of being cut off in the midst of a race to build advanced AI systems are not unfounded. —semafor.com, 8 Dec. 2025

Word History

First Known Use

1648, in the meaning defined above

Rhymes for unfounded

• abounded
• astounded
• compounded
• confounded
• expounded
• foregrounded
• impounded
• propounded
• rebounded
• resounded
• subrounded
• surrounded

Kids Definition

unfounded

adjective

un·​found·​ed ˌən-ˈfau̇n-dəd 

ˈən-

: lacking a sound base : groundless

unfounded suspicions