The most common and most likely answer to this crossword clue is the 9 letter word ELEVATION
I've seen this crossword clue in The Guardian
E
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V
A
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More clues leading to the result ELEVATION
- Height of delight about English verse
- Promotion leads to envy veiled in delight
- Height of joy welcoming European Quintet
- Joy about English victory and promotion
- Part of plans for promotion?
- Joy surrounding English vicar’s first promotion
- Architect’s plan for advancement
- Not a plan for promotion
- Promotion? No – leave it out!
- Face lift?
Buddy explains!

The straight part
We know that "promotion" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case promotion = elevation.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 ELEVATION mean?
ELEVATION noun- The act of raising from a lower place, condition, or quality to a higher; said of material things, persons, the mind, the voice, etc.
- The condition of being or feeling elevated; heightened; exaltation.
- That which is raised up or elevated; an elevated place or station.
- The distance of a celestial object above the horizon, or the arc of a vertical circle intercepted between it and the horizon; altitude.
- The measured vertical distance from the peak of a mountain or hill to its bordering lowlands.
- The angle which the gnomon makes with the substylar line.
- The movement of the axis of a piece in a vertical plane; also, the angle of elevation, that is, the angle between the axis of the piece and the line of sight; distinguished from direction.
- A geometrical projection of a building, or other object, on a plane perpendicular to the horizon; orthographic projection on a vertical plane; called by the ancients the orthography.
- The raising of the host—representing Christ’s body—in a mass or Holy Communion service.