A raincoat - from Birmingham, actually (3)
I believe the answer is:
mac
'a raincoat' is the definition.
(macintosh is a type of raincoat)
'from birmingham actually' is the wordplay.
'from' says the answer is hidden in the clue.
'MAC' is hidden in the letters of 'birmingham actually'.
(Other definitions for mac that I've seen before include "It may help you keep dry" , "one used in shower?" , "Raincoat (colloq.)" , "laptop?" , "Waterproof coat (colloq.)" .)