adj.无理由的,无根据的,平白无故,飞,莫须有
A ministry official described the report as groundless.
一位部级官员称这篇报道纯属子虚乌有。
His fears might be groundless.
他的担心也许毫无根据。
Our fears proved groundless.
我们的担心证明是毫无道理的。