1.
coupon; voucher; discount ticket
A ticket or certificate that entitles the holder to a discount, freebie, or special offer, commonly distributed by stores, restaurants, and online services.
Compound of クーポン (coupon, from French/English) and 券 (ticket; certificate). Strictly speaking, クーポン alone already means coupon, so クーポン券 is somewhat redundant, but this full form is extremely common in everyday Japanese, especially for physical paper coupons.
Common collocations
Usage
In casual speech and digital contexts, the shorter クーポン is increasingly common. The full form クーポン券 is preferred when referring to physical paper coupons or in more formal commercial contexts.