Translation guide
Describes something without a basis in fact or reason, such as fears, rumors, or accusations.
Expressing that a claim, fear, or suspicion has no factual foundation.
The most direct and common way to say 'groundless'. Used for fears, rumors, accusations, etc.
それは根拠のない噂だ。
That's a groundless rumor.
彼の不安は根拠のないものだった。
His anxiety turned out to be groundless.
Emphatic version of 根拠のない, meaning 'without any basis whatsoever'.
彼の批判は何の根拠もない。
His criticism is completely groundless.
Means 'nonsense' or 'unfounded'. More colloquial and can imply the statement is not only groundless but also absurd.
Do not translate 'groundless' as 地面のない (jimen no nai), which means 'without ground/soil' and is incorrect.
A stronger, more formal term meaning 'completely unfounded' or 'without factual basis'. Often used in legal or official contexts.
その報道は事実無根です。
That report is completely groundless.
そんな話はでたらめだ。
That story is groundless nonsense.