Ted and Oscar reuniting old soldiers (8)
I believe the answer is:
redcoats
'old soldiers' is the definition.
'ted and oscar reuniting' is the wordplay.
'and' is a charade indicator (letters next to each other).
'reuniting' indicates an anagram (letters are put together again in a new way).
'ted' put after 'oscar' is 'oscarted'.
'oscarted' with letters rearranged gives 'REDCOATS'.
(Other definitions for redcoats that I've seen before include "Old British soldiers in colourful uniforms" , "British soldiers during the American revolution" , "men who used to fight for Britain" .)