Scorch the ears badly (4)
I believe the answer is:
sear
'scorch' is the definition.
('sear' can be a synonym of 'scorch')
'the ears badly' is the wordplay.
'badly' indicates an anagram.
'ears' is an anagram of 'SEAR'.
(Other definitions for sear that I've seen before include "Withered" , "Scorch or burn the surface of" , "Burn briefly" , "Scorch, brand" , "Make very hot and dry" .)