Swift brute rolled dried grass over holes (5)
I believe the answer is:
yahoo
'swift brute' is the definition.
(I've seen this in another clue)
'rolled dried grass over holes' is the wordplay.
'rolled' says the letters should be written backwards (letters roll back).
'dried grass' becomes 'hay' (I've seen this before).
'over' says to put letters next to each other (in a down clue, some letters go over others).
'holes' becomes 'OO' (two O's - O looks like a hole).
'hay' written backwards gives 'yah'.
'yah'+'oo'='YAHOO'
(Other definitions for yahoo that I've seen before include "Swift brute" , "Uncivilised brute(Swift)" , "Boorish lout (after Swift)" , "Exclamation of joy; brute" , "Ugly swipe at delivery" .)