Grasp mat shoved over to conceal labels (6)
I believe the answer is:
stamps
'labels' is the definition.
(names or labels stamped onto something)
'grasp mat shoved over to conceal' is the wordplay.
'to conceal' indicates a hidden word.
'over' is a reversal indicator.
'spmats' can be found hidden inside 'grasp mat shoved'.
'spmats' in reverse letter order is 'STAMPS'.
(Other definitions for stamps that I've seen before include "Items of interest to a philatelist" , "Cuts out with a die" , "Brings foot down heavily onto the ground" , "Tramples" , "Postal tokens" .)