Get by out of uniform (3)
I believe the answer is:
buy
'get' is the definition.
(buying is a kind of getting)
'by out of uniform' is the wordplay.
'out of' indicates putting letters inside.
'uniform' becomes 'u' (phonetic alphabet: alpha, bravo, charlie etc.).
'by' enclosing 'u' is 'BUY'.
(Other definitions for buy that I've seen before include "Procure" , "Purchase" , "Accept truth of (colloq.)" , "Get" .)