What is Coin ?
Coin is (noun) a piece of metal money I found a 50p coin in the street. He hid the gold coins under his bed. This machine only takes 10p coins.(verb) to invent a new word or phrase They coined the phrase ‘surfing the net’ to mean searching for information on the Internet. to coin a phrase used in order to emphasise that you are saying something which is a normal everyday expression (informal.) ‘It never rains but it pours’ – to coin a phrase. (formal.) cognisant of knowing, being
source: Easier English, Student Dictionary Upper Intermediate Level