Scrambled egg, a great amount (9)
I believe the answer is:
aggregate
'amount' is the definition.
(I know that aggregate is a more specific form of the action amount)
'scrambled egg a great' is the wordplay.
'scrambled' indicates an anagram.
'egg'+'a'+'great'='eggagreat'
'eggagreat' is an anagram of 'AGGREGATE'.
(Other definitions for aggregate that I've seen before include "Sum total" , "Accumulation" , "A whole formed by combining several elements" , "All - broken stone put in cement" , "The whole amount" .)