The most common and most likely answer to this crossword clue is the 10 letter word FRIENDSHIP
I've seen this crossword clue in Independent
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More clues leading to the result FRIENDSHIP
- . What China offers last boat after end of week at work
- Quaker’s joint alliance
- Amity shown by female diner relaxed on liner
- One may want camaraderie if NHS pride gets hurt
- Relationship with China?
- Finished public relations exercises for goodwill
- Devil’s in the know about Republican alliance
- Attachment finishes on Friday — start to cheer
- Association of crooks crowding the middle of strip joint
Buddy explains!

The straight part
We know that "alliance" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case alliance = friendship.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 FRIENDSHIP mean?
FRIENDSHIP noun- The condition of being friends.
- A friendly relationship, or a relationship as friends.
- Good will.