Resembling, containing, or related to coins; having coin-like qualities or characteristics.
From coin + -y (adjective suffix). A descriptive adjective formed from the noun 'coin' to indicate coin-related properties.
You'll rarely see 'coiny' in published writing because it sounds awkward, yet numismatists (coin collectors) understand it instantly—it's one of those words that should exist more often than it does.
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