Horse turf tipped to be ready (4)
I believe the answer is:
dosh
'be ready' is the definition.
(I've seen this before)
'horse turf tipped' is the wordplay.
'horse' becomes 'H' (abbreviation as in horse power).
'turf' becomes 'sod' (both can mean a piece of grass).
'tipped' says the letters should be written backwards (letters tipped over).
'h'+'sod'='hsod'
'hsod' reversed gives 'DOSH'.
'to' is the link.
(Other definitions for dosh that I've seen before include "Money (sl.)" , "Bread - gravy - dough" , "Lolly (slang)" , "Shod (anag.)" , "Ready" .)