A wound spring letting its power out. The clock ticks, the music box plays, and all the time the store inside is going down. When it is gone the hands stop in the middle of the hour — not broken, just empty, waiting for someone to wind it back up. One way to hold this word is that slow slide from full to spent, with nobody putting anything back.
可以想成一根上緊的發條正在把力氣放出去。鐘在走、音樂盒在響，裡面存的那份力氣同時一點一點在少。放完的時候，指針就停在半路上——它沒有壞，只是空了，等著有人把它上緊回去。這個字可以用這個畫面來記：從滿到空的那一段慢慢的下滑，而且中間沒有人補回去。
From the word’s history
Deverbal from the phrasal verb run down.
這個形容詞是從動詞片語 run down 變成的（Wiktionary 記為 deverbal from run down）。所以每個用法底下都還聽得到那個動作：一路走、一路耗，耗到底。
Wiktionary entry for run-down (etymology: Deverbal from run down), supplied in the evidence packet
登入就可以看每一支怎麼連回核心畫面。