Manky is a very informal British word for something that looks dirty, stained, a bit wet or worn, and frankly not nice to touch — a manky towel, manky trainers, a manky fridge shelf. It is closer to “grotty” or “rank” than to a calm, polite “dirty.” Friends say it; a job interview does not. Americans almost never use it. Though actually, people also stretch it to mean “inferior, a bit rubbish,” not only physically filthy: a manky old phone can just be a sad, cheap one. It can sound slightly disgusted, but among British speakers it is often light and jokey rather than a hard insult. It is not related to man. If you are writing school English for an international exam, choose dirty, stained, or messy instead, unless you are showing British talk on purpose.

髒兮兮的、邋遢噁心（英式口語；台灣沒有固定對應詞）