Slide around cap (3)
I believe the answer is:
lid
'cap' is the definition.
(eg the lid of a bottle)
'slide around' is the wordplay.
'around' says the answer is hidden in the clue.
'LID' can be found hidden inside 'slide'.
(Other definitions for lid that I've seen before include "Top or cover" , "Top crust of pie" , "Removable cover of a container" , "Pie crust; cover" , "Bottle or jar top" .)