Surgical tool reshapes large ears (5)
I believe the answer is:
laser
'surgical tool' is the definition.
(I've seen this in another clue)
'reshapes large ears' is the wordplay.
'reshapes' is an anagram indicator (I've seen 'reshaped' mean this).
'large' becomes 'L' (eg in clothes sizes).
'l'+'ears'='lears'
'lears' is an anagram of 'LASER'.
(Other definitions for laser that I've seen before include "Intense light generator" , "light-intensifier" , "modern light industry" , "E.g. surgical light-beam" , "Optical device producing an intense beam of light" .)