Category, sort (4)
I believe the answer is:
type
I believe this is a double definition.
'category' is the first definition.
(I know that type is a type of form)
'sort' is the second definition.
(I know that type is a type of sort)
(Other definitions for type that I've seen before include "of a certain kind" , "Print form" , "Use a keyboard; sort" , "Kind; set in print" , "Genre" .)