B1 削价出售的，特价销售的，特惠出售的
If goods in a shop are on (special) offer, they are being sold at a lower price than usual.
Strawberries were on special offer today so I bought loads of them.
Try not to buy stuff you don't need just because it's on offer.
I usually wait till they're on special offer and then stock up.
I notice champagne is on offer this week.
It has some really good wines on offer at the moment.
See also: offer noun