A coin is defined as a round piece of money of a certain value.(noun)
An example of a coin is a dime.
The definition of coin is requiring round pieces of money to use.(adjective)
An example of coin used as an adjective is in the phrase "a coin washing machine," which means a washing machine that requires payment in coins to use it.
Coin means to make metal money, or to come up with something new.(verb)
See coin in Webster's New World College Dictionary
Origin: ME < OFr coin, coigne, a wedge, stamp, corner < L cuneus, a wedge < IE base *kū-, pointed > OIr cuil, L culex, gnat, Avestan sū-kā, needle
See coin in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old French, die for stamping coins, wedge
Origin: , from Latin cuneus, wedge.
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