Native and I go in with bear: that's mad (9)
I believe the answer is:
aborigine
'native' is the definition.
(I've seen this before)
'i go in with bear that's mad' is the wordplay.
'with' says to put letters next to each other.
'that's mad' indicates anagramming the letters.
'i'+'go'+'in'+'bear'='igoinbear'
'igoinbear' with letters rearranged gives 'ABORIGINE'.
'and' acts as a link.
(Other definitions for aborigine that I've seen before include "Original inhabitant" , "Oldest inhabitant" , "Early Australian" , "Old Australian" , "Native Australian" .)