Bill seen in Dunstable (3)
I believe the answer is:
tab
'bill' is the definition.
(a tab is a bill at a bar)
'in dunstable' is the wordplay.
'in' says the answer is hidden in the clue.
'TAB' can be found hidden inside 'dunstable'.
'seen' is the link.
(Other definitions for tab that I've seen before include "ticket" , "Tag" , "Text indent key" , "Tally of orders in bar" , "Tally at bar (colloq.)" .)