noun
welcome rain in a drought; timely relief
A yojijukugo literally meaning 'merciful rain under a drought sky'; used figuratively for any long-awaited help or relief.
長い干ばつの後、旱天慈雨がようやく降り注いだ。
After a long drought, welcome rain finally poured down.
彼の支援はまさに旱天慈雨だった。
His support was truly a welcome relief.
A yojijukugo composed of 旱天 (drought sky) and 慈雨 (merciful rain). The exact origin is uncertain, but it follows a classical Chinese-derived pattern of four-character idioms.