A mechanism for intercepting and logging network traffic.(noun)
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Use "sniffer" in a sentence
"But, he, the sniffer, is not considered, what's replaced his role is some theoretical bogey man."
"My sniffer is barely able to pick up the smell of a T-bone on a grill."
"In separate federal court filings last night here, plaintiffs in the TJX case provided additional information showing how computer hackers, using a data-capturing program called a "sniffer" -- may have been able to steal more than 100 million cards."