moulder
/ˈməʊldə(r)/( <美> molder)
verb
no obj.［often as adj. mouldering］
- slowly decay or disintegrate, especially because of neglect（尤指因长期被疏忽而）腐烂; 碎裂：
there was a mushroomy smell of disuse and mouldering books
有一股因长年弃置不用和发霉书籍带来的蘑菇般气味
figurative 〈喻〉I couldn't permit someone of your abilities to moulder away in a backwater.
我不能允许像你这样有能力的人在死气沉沉的地方荒废下去。
词源
mid 16th cent.: perhaps from MOULD3 , but compare with Norwegian dialect muldra 'crumble'.