Old and wise, native American (5)
I believe the answer is:
osage
'native american' is the definition.
(I've seen this before)
'old and wise' is the wordplay.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'and' says to put letters next to each other.
'wise' becomes 'sage' (similar in meaning).
'o'+'sage'='OSAGE'
(Other definitions for osage that I've seen before include "Missouri tribe; go sea (anag.)" , "Language" , "Brave" , "Age so (anag) - member of a Native American people" , "Indian people" .)