/,mɪd'stri:m; `mɪd,strim/
n [U]
1 part of a stream, river, etc half-way between its banks 中流
*There's a fast current in midstream. 中流的水很急.
2 (idm 习语) change/swap horses in midstream => horse. in midstream in the middle of an action, etc 在进行中
*The speaker stopped in midstream, coughed, then started up again. 演讲人中途停下来咳嗽, 然後又继续讲.

n[U]
in midstream
when something has started and is still happening
　They had to drop the experiment in midstream.
　He interrupted the official in midstream (=while the official was still speaking) .
the middle part of a river
in midstream
　The boat had anchored in midstream.
>midstreamadv