A public telephone that requires pre-payment to operate, generally via the insertion of coins or a credit card(noun)
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Use "payphone" in a sentence
"The payphone is the twenty-first century horse-trough."
"Promptly at two, he called the payphone outside Bloomingdale’s."
"The payphone was the type that only took dollars for every call, and frequently did funky things like drop calls or simply not work or return any change."