What is Counterfeit ?
Counterfeit is (adj) (of money, art or documents) false, not real The police have warned shopkeepers that counterfeit £20 notes are in circulation. You can see stands in Oxford Street selling counterfeit jewellery. Synonym fake. Antonym genuine(verb) to make imitation money Are the new £10 notes more difficult to counterfeit than the old ones? Only very sophisticated printing machines can be used to counterfeit banknotes. Synonym forge(noun) a thing which has been forged There is something wrong with this passport – in fact it may be a counterfeit. Synonym forgery
source: Easier English, Student Dictionary Upper Intermediate Level