Cleaner to trace out a letter (9)
I believe the answer is:
character
'a letter' is the definition.
(written character)
'cleaner to trace out' is the wordplay.
'cleaner' becomes 'char' (char can mean a cleaner).
'to' means one lot of letters go next to another.
'out' indicates an anagram (out can mean wrong or inaccurate).
'trace' is an anagram of 'acter'.
'char'+'acter'='CHARACTER'
(Other definitions for character that I've seen before include "Distinctive nature" , "Nonconformist" , "crank" , "Letter or figure" , "Type - letter" .)