Bails out chap (5)
I believe the answer is:
basil
'chap' is the definition.
'bails out' is the wordplay.
'out' indicates an anagram (out can mean wrong or inaccurate).
'bails' anagrammed gives 'BASIL'.
(Other definitions for basil that I've seen before include "A herb; --- Brush, Fawlty" , "Aromatic herb in pesto" , "Bails out the herb" , "Fellow" , "Plant; Brush; Fawlty" .)