noun
big treat; great offer; extra service
Used when a shop, business, or person provides something extra or at a special discount, often to attract customers or show generosity. Colloquial and friendly.
今日は大サービスで、全品半額です！
Today's a big treat: everything is half price!
あの店はいつも大サービスしてくれるから好きだ。
I like that shop because they always give great deals.