Amorphous dung heaps not good for spreading (8)

I believe the answer is:

unshaped

'amorphous' is the definition.
(amorphous means shapeless)

'dung heaps not good for spreading' is the wordplay.
'not' is a deletion indicator.
'good' becomes 'g' (abbreviation).
'for spreading' indicates an anagram (letters spread around).
'dung'+'heaps'='dungheaps'
'dungheaps' with 'g' taken away is 'dunheaps'.
'dunheaps' anagrammed gives 'UNSHAPED'.

(Another definition for unshaped that I've seen is " Head puns? (anag)".)

I've seen this clue in The Guardian.

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