A potato, for example, for an awful brute (5)
I believe the answer is:
tuber
'a potato for example' is the definition.
(potato is an example of a tuber)
'an awful brute' is the wordplay.
'an awful' indicates anagramming the letters.
'brute' with letters rearranged gives 'TUBER'.
'for' acts as a link.
(Other definitions for tuber that I've seen before include "Rhizome, as of potato" , "Underground stem, root" , "Root of potato etc" , "A brute of a spud" , "Fleshy underground root" .)