Some touching that hurt (4)
I believe the answer is:
ouch
'that hurt' is the definition.
(expression of pain)
'some touching' is the wordplay.
'some' indicates a hidden word (some of the parts of the word are used).
'OUCH' is hidden within 'touching'.
(Other definitions for ouch that I've seen before include "Pained expression" , "Pained exclamation" , "response to a bad pun" , "Pained cry" , "Pained sound" .)