Carry out survey going back for a measure (6)
I believe the answer is:
dollop
'a measure' is the definition.
(dollop is a kind of measure)
'carry out survey going back' is the wordplay.
'carry out' becomes 'do' ('do' can be a synonym of 'carry out').
'survey' becomes 'poll' (polling is a kind of surveying).
'going back' says the letters should be written in reverse.
'poll' backwards is 'llop'.
'do'+'llop'='DOLLOP'
'for' acts as a link.
(Other definitions for dollop that I've seen before include "Large shapeless lump" , "A shapeless lump of something soft, like dough" , "Squidgy lump (of food)" , "great lump" , "Shapeless lump (of food)" .)