9 across
Possibility
of
outlet
store
finally
opening
(5)
Possibility of outlet store finally opening (5)
hints
0
checks
0
hints
The definition is at the beginning of the clue.
How the clue works
Right, so possibility is your definition there, a happening or occurrence. Now take the last letter of "store", finally, which gives you E, and stick that at the opening — the front — of VENT (your outlet), and you've got EVENT.