Counterfeit Goods

noun a system in which goods or services are bought and sold illegally, usually to avoid government regulations or taxes

• The government is cracking down on the black market for counterfeit goods.
• I heard you can get cheap electronics on the black market.
• Don't mess with the black market, it's too risky.
• His reputation on the black market of gossip was unmatched.

noun a cheap imitation or copy of a popular product

verb to copy or imitate something, especially in a cheap or unauthorized way

• The company faced legal action for selling knock-off designer handbags.
• I bought a knock-off version of the popular sneakers to save money.
• I can't believe she's wearing a knock-off Gucci belt.
• His painting was a knock-off of a famous artist's work.