also: ひとや · ひとよ
He finished reading the book in one night.
一夜明けると、雪が積もっていた。
When morning came, snow had piled up overnight.
The two of them spent a night at the mountain cabin.
He became a celebrity overnight.
The long night finally came to an end.
rags to riches; overnight millionaire
fish salted and dried overnight
Rare reading; いちや is overwhelmingly more common.