Tips of shark's teeth: evil, edged like a sword (5)
I believe the answer is:
steel
'a sword' is the definition.
(I know that sword can be written as steel)
'tips of shark's teeth evil edged like' is the wordplay.
'tips of' suggests taking the first letters (I've seen 'tip of' mean this).
The first letters of 'sharks teeth evil edged like' is 'STEEL'.
(Other definitions for steel that I've seen before include "Knife-sharpener" , "Iron/carbon alloy" , "May be cold" , "Determination, metal" , "Hard, strong, grey alloy" .)