American soldier banks on Zoom with old device (5)
I believe the answer is:
gizmo
'device' is the definition.
(gizmo is a kind of device)
'american soldier banks on zoom with old' is the wordplay.
'american soldier' becomes 'GI' (informal term for a US soldier).
'banks on' says to hollow out the word (remove centre letters) (only the letters at the edges or banks of the word).
'with' is a charade indicator (letters next to each other).
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'zoom' with its centre removed is 'zm'.
'gi'+'zm'+'o'='GIZMO'
(Other definitions for gizmo that I've seen before include "Gadget, thingamajig" , "Ingenious device; gadget" , "Device or control that is very useful for a particular job" , "Thingamabob, gadget" .)