Entertain army (4)
I believe the answer is:
host
I believe this is a double definition.
'entertain' is the first definition.
(I know this)
'army' is the second definition.
(I know that host is a type of army)
(Other definitions for host that I've seen before include "Present" , "Provide entertainment" , "put on" , "Multitude -- MC" , "One entertains guests" .)