The most common and most likely answer to this crossword clue is the 10 letter word RECOMPENSE
I've seen this crossword clue in Independent
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More clues leading to the result RECOMPENSE
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The straight part
We know that "reward" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case reward = recompense.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 RECOMPENSE mean?
RECOMPENSE noun- An equivalent returned for anything given, done, or suffered; compensation; reward; amends; requital.
- That which compensates for an injury, or other type of harm or damage.
- To reward or repay (someone) for something done, given etc.
- To give compensation for an injury, or other type of harm or damage.
- To give (something) in return; to pay back; to pay, as something earned or deserved.