Definition of "back door" []

• A subsidiary entrance to a building or house at its rear, normally away from the street. (noun)
• A means of access, often secret and unprotected, to something. (noun)
• A secret means of access to a program or system. (noun)
• The anus, generally used in reference to anal sex. (noun)
• The path of a pitch which starts outside and then slides over the plate. (adjective)

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• "He locked the back door and whistled for Artie, who came flying around the corner of the barn, a happy grin on his big, silly dog-face."
• "So, Walt Williams the head of the High-Speed Flight Station went out and found Neil and dragged him through the back door by his ear!"
• "It didn't look like the back door to 109A had been opened in some time, which meant that the occupants of the building entered and left through the door on Main Street."