knockoff; imitation product; counterfeit product
Refers to goods that imitate a well-known brand or design, often illegally. Used in contexts of consumer goods, fashion, electronics, etc.
The bag I bought online turned out to be a knockoff.
Selling counterfeit products is prohibited by law.
Compound of コピー (copy) and 商品 (product, goods). The term is a modern loanword-based compound, likely influenced by English 'copy product' or similar phrases.