看得到的髒
最貼近字面的一組：房間、住屋、環境，髒到讓人待不下去。
adjective · C1
Very dirty and unpleasant to be in or to look at, because nobody has the money or the will to keep it clean. It is used most about rooms, buildings and the conditions people live in.
髒亂不堪
核心畫面
One way to hold this word: dirt that has been allowed to sit. Not a spill from this morning, but damp in the walls, rubbish nobody carries out, a place that has been left alone for months. The word always carries that second part — someone could have cleaned this and did not. That is what lets it move off walls and onto what people do, so a deal can be squalid in exactly the way a room is.
squalid 可以想成「放著沒人管，慢慢積起來的髒」。不是今天早上打翻的一杯水，而是牆上的霉、沒人倒的垃圾、幾個月…更多收起
squalid 可以想成「放著沒人管，慢慢積起來的髒」。不是今天早上打翻的一杯水，而是牆上的霉、沒人倒的垃圾、幾個月沒修的水管。這個字裡一定有第二層：本來有人可以處理，但沒有。就是這一層讓它離得開牆壁。當一筆交易被說成 squalid，講的也是同一件事——上不了檯面，而且大家都知道卻放著。From the word’s history
Learned borrowing from Latin squalidus, from squalere meaning to be rough or dirty, and related to the noun squalor. So roughness and built-up dirt were in the word from the start.
squalid 是從拉丁文 squālidus 借進英文的，來自動詞 squālēre，意思是「又粗又髒」。同一條線上還有拉丁文 squālor，也就是今天英文的 squalor。所以「表面粗糙、積著髒東西」不是後來的引申，而是這個字本來的意思，兩個現代用法都從這裡出發。
Wiktionary via kaikki snapshot 3f6f69a190036ae4, squalid etymology 1: Learned borrowing from Latin squālidus, from squālēre (to be rough or dirty); related Latin squālor
Two branches
行為上的髒
同樣一層「積起來的髒」，搬到人做的事情上：不是驚天動地的壞，而是又小又難看、見不得光的那種。這是比喻上的延伸，不是另一個來源。
adjective · C1
Dishonest or morally low in a small, shabby way — used about behaviour, deals and secrets that people would be ashamed to have made public.
卑劣的