olemus
(a) äralõigatav osa, füüsiline või virtuaalne
(b) soodustust pakkuv turunduslik pilet
Wiktionary:
1. a section of a ticket, showing the holder to be entitled to some specified accommodation or service, as to a passage over a designated line of travel, a particular seat in a theater, a discount, etc
2. a voucher issued by a manufacturer or retailer which offers a discount on a particular product

näiteid
https://duckduckgo.com/?q=coupon&t=h_&iax=images&ia=images

ülevaateid
https://en.wikipedia.org/wiki/Coupon

turvalisus
https://www.mylawquestions.com/what-is-coupon-fraud.htm
https://www.trendmicro.com/en_us/research/17/i/business-process-compromise-underground-coupon-fraud.html
https://payback-ltd.com/blogs/fake-coupons-scam/