Camp entertainer is an old soldier (7)
I believe the answer is:
redcoat
I believe this is a double definition.
'camp entertainer' is the first definition.
(I've seen this before)
'an old soldier' is the second definition.
(I've seen this before)
'is' is the link.
(Other definitions for redcoat that I've seen before include "British soldier and holiday camp worker" , "British soldier (hist.)" , "Old British soldier - Butlin's entertainment organiser" , "British soldier or Butlin's worker" , "Old-time British soldier" .)