Very much a lack of purpose (2,3)
I believe the answer is:
no end
'very much' is the definition.
(thesaurus)
'a lack of purpose' is the wordplay.
'a lack of' becomes 'no' (lack of money is no money).
'purpose' becomes 'end' (I've seen this before**).
'no'+'end'='NO END'
(Other definitions for no end that I've seen before include "Very much (colloq.)" , "Non-stop" , "goalless?" , "what eternity offers?" , "Without limit" .)