Discount event (4)
I believe the answer is:
sale
'discount event' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for sale that I've seen before include "Offer period" , "Retail event - town in Greater Manchester" , "Disposal of shop's stock at reduced prices" , "Bargain-price event" , "Auction; Cheshire town" .)