Literally: above – leak – below – damp
Alternately: A poverty-stricken household; a dilapidated house. Water leaks in from above when it rains, and damp seeps up from below; a double threat not to be taken lightly in any region with a rainy season, especially if the houses are mostly made of wood frame, straw mats, and paper walls.
Notes: 湿 may also be pronounced shitsu without any change in meaning.
This phrase comes to us from the writings of our friend, Warring States era philosopher Zhuangzi (a.k.a. Zhuang Zhou) (Japanese 荘子, Soushi). Unlike some sayings and yojijukugo derived from the Chinese classics, today’s compound seems to be relatively rare in Japan.