Meaning of “coin” - Learner’s Dictionary

coin

noun uk us /kɔɪn/

B1 [ C ] a flat, usually round, piece of metal used as money:

a pound coin
toss a coin

to throw a coin into the air so that it turns over several times, and see which side it lands on, often in order to make a decision

(Definition of “coin noun” from the Cambridge Learner’s Dictionary © Cambridge University Press)