One after the other destined, it’s said, for detention (10)
I believe the answer is:
internment
'detention' is the definition.
(internment is a kind of detention)
'one after the other destined it's said' is the wordplay.
'one after the other' becomes 'intern' (I am not sure about this - if you are sure you should believe this answer much more).
'destined' becomes 'meant' (meaning is a kind of destining).
'it's said' indicates a 'sounds like' (homophone) clue.
'meant' is a homophone of 'ment'.
'intern'+'ment'='INTERNMENT'
'for' acts as a link.
(Other definitions for internment that I've seen before include "Locking up" , "Detention" , "Committal" , "Confinement of an enemy national" , "Precautionary measure" .)