The most common and most likely answer to this crossword clue is the 12 letter word DISPLACEMENT
I've seen this crossword clue in The Daily Telegraph
D
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S
P
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A
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More clues leading to the result DISPLACEMENT
Buddy explains!

The straight part
We know that "Moving" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case moving = displacement.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 DISPLACEMENT mean?
DISPLACEMENT noun- The act of displacing, or the state of being displaced; a putting out of place.
- The quantity of a liquid displaced by a floating body, as water by a ship, the weight of the displaced liquid being equal to that of the displacing body.
- The process of extracting soluble substances from organic material and the like, whereby a quantity of saturated solvent is displaced, or removed, for another quantity of the solvent.
- Moving the target to avoid an attack; dodging.
- A vector quantity which denotes distance with a directional component.
- (grammar) The capability of a communication system to refer to things that are not present (that existed or will exist at another time, or that exist at another location).