COIN may refer to:

• Collaborative innovation network, innovative teams
• Counter-insurgency

A coin is a piece of hard material used primarily as a medium of exchange or legal tender. They are standardized in weight, and produced in large quantities at a mint in order to facilitate trade. They are most often issued by a government.

Coín is a town and municipality in the Province of Málaga, Spain, c. 33 km west of the provincial capital, Málaga, and about 30 km north of Marbella. The town has an official population of 22,000 inhabitants.