There's a terrible risk you could injure someone with it! (4)
I believe the answer is:
kris
'you could injure someone with it' is the definition.
I can't judge whether this definition defines the answer.
'there's a terrible risk' is the wordplay.
'there's a terrible' indicates an anagram.
'risk' anagrammed gives 'KRIS'.
Can you help me to learn more?
(Other definitions for kris that I've seen before include "Wavy-edged dagger" , "Malayan slashing knife" , "Malaysian knife with a scalloped edge" , "Malay knife" , "-- Kringle, Santa Claus" .)