noun
Refers to liquid or moisture gradually leaking or oozing out, often through a surface or material.
壁からの染み出しがひどくなってきた。
The seepage from the wall has gotten worse.
この容器は染み出しを防ぐ設計です。
This container is designed to prevent seepage.
漏れ is a general term for leakage, while 染み出し specifically implies slow oozing or seepage through a material.
Compound of 染み (stain, seep) and 出し (putting out), from the verb 染み出す (to ooze out).