The most common and most likely answer to this crossword clue is the 11 letter word TRIBUTARIES
I've seen this crossword clue in The Daily Telegraph
T
R
I
B
U
T
A
R
I
E
S
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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 TRIBUTARIES mean?
TRIBUTARIES noun- A natural water stream that flows into a larger river or other body of water.
- A nation, state, or other entity that pays tribute.