| 河清 | [かせい, kasei] (n) clearing of the river water [Add to Longdo] |
| 百年河清 | [ひゃくねんかせい, hyakunenkasei] (exp) waiting for one hundred years for the waters of the Yellow River to clear; waiting in vain for an unlikely event; waiting for pigs to fly; When the sky falls, we shall catch larks [Add to Longdo] |