Detach (8)
'detach' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for unpin that I've seen before include "free" , "Loosen" , "release" , "Things tied together" , "Remove fastening from" .)
(Other definitions for hive off that I've seen before include "Divert assets" , "Sell" , "Separate (something) from larger group" .)
'detach' is the definition.
(I know that detach is a kind of separate)
This is all the clue.
(Other definitions for separate that I've seen before include "Dinstinct or discrete" , "Not joined or united with others" , "Break up" , "Not joined or touching" , "Take or keep apart" .)