Old men host TV show (4,4)
I believe the answer is:
dads army
'tv show' is the definition.
'dads army' can be an answer for 'show' (I've seen this before). I am not certain of the 'tv' bit.
'old men host' is the wordplay.
'old men' becomes 'dads' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'host' becomes 'army' (both can mean a large number of people).
'dads'+'army'='DADS ARMY'
Can you help me to learn more?
(Other definitions for dads army that I've seen before include "TV programme" , "British sitcom featuring the Home Guard" , "Show" , "Evergreen TV comedy" .)