Cold stuff in the Arctic, evidently
I believe the answer is:
ice
'cold stuff' is the definition.
(I've seen this before)
'in the arctic evidently' is the wordplay.
'in' says the answer is hidden in the clue.
'ICE' can be found hidden inside 'arctic evidently'.
(Other definitions for ice that I've seen before include "To put in a drink or slide on" , "Diamonds (sl)" , "Being feeble, can't cut any" , "Finish decorating the Christmas cake" , "Solid H2O" .)