Order some frozen joints (6)
I believe the answer is:
enjoin
'order' is the definition.
('enjoin' can be a synonym of 'order')
'some frozen joints' is the wordplay.
'some' says the answer is hidden in the clue (some of the parts of the word are used).
'ENJOIN' can be found hidden inside 'frozen joints'.
(Other definitions for enjoin that I've seen before include "Advise" , "Order, urge" , "Urge (to do something)" , "Prohibit by order" , "Command (legal)" .)