A tiller reworked to be exact (7)
I believe the answer is:
literal
'be exact' is the definition.
(similar in meaning)
'a tiller reworked' is the wordplay.
'reworked' indicates anagramming the letters.
'a'+'tiller'='atiller'
'atiller' with letters rearranged gives 'LITERAL'.
'to' acts as a link.
(Other definitions for literal that I've seen before include "All tire (anag.)" , "Following the exact meaning" , "Word-for-word" , "Actual" , "Precise" .)