coin 
(koin)
(koin)n.
1. A small piece of metal, usually flat and circular, authorized by a government for use as money.
2. Metal money considered as a whole.
3. A flat circular piece or object felt to resemble metal money: a pizza topped with coins of pepperoni.
4. A mode of expression considered standard: Two-word verbs are valid linguistic coin in the 20th century.
5. Variant of quoin.
tr.v. coined, coin·ing, coins
1. To make (pieces of money) from metal; mint or strike: coined silver dollars.
2. To make pieces of money from (metal): coin gold.
3. To devise (a new word or phrase).
adj.
Idiom: Requiring one or more pieces of metal money for operation: a coin washing machine.
the other side of the coin
One of two differing or opposing views or sides.
[Middle English, from Old French, die for stamping coins, wedge, from Latin cuneus, wedge.]
coina·ble adj.
coiner n.