The most common and most likely answer to this crossword clue is the 9 letter word ALLIANCES
I've seen this crossword clue in The Daily Telegraph
A
L
L
I
A
N
C
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 ALLIANCES mean?
ALLIANCES noun- The state of being allied.
- The act of allying or uniting.
- A union or connection of interests between families, states, parties, etc., especially between families by marriage and states by compact, treaty, or league.
- Any union resembling that of families or states; union by relationship in qualities; affinity.
- (with the definite article) The persons or parties allied.