A hollow or empty space; a cavity or void.
古い木の幹は中が虚ろになっていた。
The old tree's trunk had become hollow inside.
岩の裂け目に小さな虚ろが見えた。
I could see a small hollow in the crack of the rock.
歯の治療で虫歯の虚ろを埋めてもらった。
At the dental treatment they filled the cavity caused by tooth decay.
A hollow or vacant expression, voice, or look; appearing blank or empty (emotionally or mentally).
彼は何日も寝込んでいて、目が虚ろになっていた。
He had been lying in bed for days, and his eyes looked vacant.
虚ろな笑顔で話すだけで、心から楽しんでいる様子はなかった。
She only spoke with a hollow smile and didn't seem genuinely happy.
長い説明を聞いていると、彼の表情が次第に虚ろになった。
As he listened to the long explanation, his expression gradually became vacant.
言葉だけで埋め合わせようとしても、胸の虚ろは消えなかった。
Trying to make up for it with words didn't fill the emptiness in his heart.