Giant fled, somehow shrinking (9)

I believe the answer is:

deflating

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'shrinking' is the definition.
The answer and definition can be both related to change as well as being present participle verbs.
Maybe they are linked in a way I don't understand?

'giant fled somehow' is the wordplay.
'somehow' indicates an anagram.
'giant'+'fled'='giantfled'
'giantfled' with letters rearranged gives 'DEFLATING'.

Can you help me to learn more?

(Another definition for deflating that I've seen is " Letting the air out".)

I've seen this clue in The Mirror.

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