Device that could be tagged (6)
I believe the answer is:
gadget
'device' is the definition.
(gadget is a kind of device)
'could be tagged' is the wordplay.
'could be' indicates anagramming the letters.
'tagged' anagrammed gives 'GADGET'.
'that' is the link.
(Other definitions for gadget that I've seen before include "Small mechanical device or tool" , "Clever device" , "Gismo" , "Useful small device" , "appliance" .)