The most common and most likely answer to this crossword clue is the 9 letter word MIDSTREAM
I've seen this crossword clue in The Times
M
I
D
S
T
R
E
A
M
More clues leading to the result MIDSTREAM
- Part of flower trimmed, as going to seed
- Part of flower's trimmed, as in a tangle
- Star mimed, unexpectedly, halfway through
- Timers attached to dam repositioned away from the banks
- Mad terms I amended half way through
- Knight quits Mastermind, unexpectedly, halfway through
- Star mimed, badly, halfway through
- The farthest one will be from a bank
- Half way through, I'd stammer incoherently
- Mister mad to swim where current may be the strongest
Buddy explains!

The straight part
We know that "Part of flower" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case part of flower = midstream.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does MIDSTREAM mean?
MIDSTREAM noun- The middle of a stream or river.