1N-UNCOUNT [oft inNOUN]中流;河流中心 Someone or something that is in midstream is in the middle of a river, where the current is strongest. 中流;河流中心
Their boat had capsized in midstream.
他们的船在河中央翻了。
Midstream is also an adverb.
Some of them got caught midstream by the tide.
他们中的一些人被潮水困在了河中央。
2N-UNCOUNT [oft inNOUN](事情的)半途,半路,一半 If someone who has been doing something such as talking stops or pauses in midstream, they stop doing it, often before continuing. (事情的)半途,半路,一半
I was cut off in midstream.
我说到一半时被打断了。
Midstream is also an adverb.
The most difficult thing in a fast game of rugby is to change course midstream.