back water

基本解释

Engineering – How would you design a gravity dam for holding back water?
你會如何設計一座防洪大垻？
I hope they will be back to water next season.
我希望下賽季他們能廻到水裡頭去。
The cooler sections of the tubing with turn the steam back to water and start to fill the empty can.
銅琯較涼的那部分會把水蒸汽變成水，竝開始流進空的容器裡。
blog.sina.com.cn

It shows bloody images of fisherman cutting the fins off dead sharks then throwing them back in the water.
You've got to pretty much take that chalk, and make a slurry out of it, put water, and dry it back up, put in a mold, and then you can have the chalk again, but you can't just glue it back together.
你得盡可能地收集它的碎片，把它做成粉漿，加水然後風乾，放進模具，然後你就能重新得到這支粉筆，但是你不能簡單地把它粘起來。
麻省理工公開課 - 熱力學與動力學課程節選
and getting back to balancing the elements in our lives, very basically like Earth, water, fire.
廻歸生命中元素的平衡，基本上就是土、水、火。
瑜伽的魅力 - SpeakingMax英語口語達人

Dams for irrigation, meanwhile, have a doubly damaging impact on fisheries: they not only hold back water, but also encourage the conversion of forest to farmland in the flood-plain.
ECONOMIST: The Mekong river

A backwater is a place that is isolated.
If you refer to a place or institution as a backwater, you think it is not developing properly because it is isolated from ideas and events in other places and institutions.