Dig starters of parsnip, liver and octopus — yuck! (6)
I believe the answer is:
plough
'dig' is the definition.
(plough can mean to dig into something)
'starters of parsnip liver and octopus yuck' is the wordplay.
'starters of' indicates taking the first letters.
'and' is a charade indicator (letters next to each other).
'octopus' becomes 'o' (this might be a standard abbreviation of which I'm unaware).
'yuck' becomes 'ugh!'.
The initial letters of 'parsnip liver' is 'pl'.
'pl'+'o'+'ugh'='PLOUGH'
(Other definitions for plough that I've seen before include "Furrower of soil" , "prepare the ground" , "that produces agricultural turnover" , "till" , "break new ground, perhaps" .)