The most common and most likely answer to this crossword clue is the 7 letter word RIVULET
I've seen this crossword clue in The Guardian
R
I
V
U
L
E
T
More clues leading to the result RIVULET
- Stream game, holding a number by restraint
- Head of Radio Four, posh, hired junior banker
- Burn fuel occasionally in entrance
- Gill having to concentrate, east going for rubber
- Compel attention about empty urinal producing stream
- A lot of split rubber beginning to thin and burn
- Channel Four’s in guide shown by TV, but not Five
- Rugby quartet included allowed stream
Buddy explains!

The straight part
We know that "stream" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case stream = rivulet.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 RIVULET mean?
RIVULET noun- A small brook or stream; a streamlet.
- Perizoma affinitatum, a geometrid moth.