Operative undertaking to block backing of corporation (8)
I believe the answer is:
factotum
'operative' is the definition.
The definition and answer can be both people as well as being singular nouns.
Maybe there's an association between them I don't understand?
'undertaking to block backing of corporation' is the wordplay.
'undertaking' becomes 'act' (I've seen this in another clue).
'to block' is an insertion indicator (block can mean to fill a hole in something).
'backing' says the letters should be written in reverse.
'corporation' becomes 'tum' ('corporation' is a humorous term for stomach fat).
'of' back-to-front is 'fo'.
'act' inserted into 'fo' is 'facto'.
'facto'+'tum'='FACTOTUM'
Can you help me to learn more?
(Other definitions for factotum that I've seen before include "General servant" , "Odd-job servant" , "Employee who does many jobs" , "junior official" , "Man of all work" .)