Reporter's funny bone (7)
I believe the answer is:
humerus
'bone' is the definition.
(humerus is a kind of bone)
'reporter's funny' is the wordplay.
'reporter's' shows a homophone (sound like) (report can mean to speak something aloud).
'funny' becomes 'humorous' ('humorous' can be similar in meaning to 'funny').
'humorous' is a homophone of 'HUMERUS'.
(Other definitions for humerus that I've seen before include "Boneo of the upper arm" , "Arm bone (that sounds comical)" , "Bone from shoulder to elbow" , "What's often thought funny" , "Bone that sounds funny?" .)