Less sensitive figure, me (6,3)
I believe the answer is:
number one
'me' is the definition.
(I've seen this before)
'less sensitive figure' is the wordplay.
'less sensitive' becomes 'number' (numb means insensitive or unfeeling).
'figure' becomes 'one' (a numerical figure).
'number'+'one'='NUMBER ONE'
(Other definitions for number one that I've seen before include "officer on board?" , "Top-of-the-charts hit" , "Cut" , "Informally and numerically, oneself" , "Yours truly" .)