The most common and most likely answer to this crossword clue is the 9 letter word BAKSHEESH
I've seen this crossword clue in The Times
B
A
K
S
H
E
E
S
H
More clues leading to the result BAKSHEESH
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The straight part
We know that "tip" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case tip = baksheesh.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 BAKSHEESH mean?
BAKSHEESH noun- In the Middle East, southwest Asia and Eastern Europe: a bribe or tip.
- A minor wound that is severe enough to get a soldier sent away from the front.
- To bribe with a baksheesh.