Categorised (11)
'categorised' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for pigeonholed that I've seen before include "Assigned rigidly to a role (with a bird)" , "neatly put away" .)
(Other definitions for filed that I've seen before include "Placed in folder" , "Worked with a tool" , "Noted" , "arranged in a particular way" , "Put away in a container for records" .)