The most common and most likely answer to this crossword clue is the 10 letter word EXALTATION
I've seen this crossword clue in Independent
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More clues leading to the result EXALTATION
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The straight part
We know that "Joy" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case joy = exaltation.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 EXALTATION mean?
EXALTATION noun- The act of exalting or raising high; also, the state of being exalted; elevation.
- The refinement or subtilization of a body, or the increasing of its virtue or principal property.
- That placement of a planet in the zodiac in which it is deemed to exert its strongest influence.
- The collective noun for larks.
- An abnormal sense of personal well-being, power, or importance, observed as a symptom in various forms of insanity.