Army in triumph, ostensibly (4)

I believe the answer is:

host

'army' is the definition.
(I know that host is a type of army)

'in triumph ostensibly' is the wordplay.
'in' indicates a hidden word.
'HOST' is hidden within 'triumph ostensibly'.

(Other definitions for host that I've seen before include "TV presenter; large number" , "One receiving guests" , "Party-giver" , "Multitude -- MC" , "Multitude - emcee" .)

I've seen this clue in The Telegraph.

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