a door at the rear of a house, building, etc.: Fans were waiting by the backdoor of the theater, hoping to catch a glimpse of the band.
a secret, furtive, or illicit manner or means: The business has a backdoor through which the board of directors can access slush fund money.
an indirect manner or means: Marriage counseling was a kind of backdoor into therapy, where I finally faced my dysfunctional relationship with my mother.
Computers. a secret access point or undocumented vulnerability in a software program, hardware component, or digital network, sometimes intentionally maintained as for remote developer access, but also sometimes created or exploited for unauthorized access by hackers: If half of all devices have disclosed backdoors, cybersecurity experts must assume that the number of devices affected by undisclosed or malicious backdoors is much higher.
Slang: Usually Vulgar. anus.
adjective Also back-door .
secret; furtive; illicit: Special interests pushed through a backdoor contract before the bidding period had expired.
indirect: The immigration reform bill included backdoor amnesty for employed undocumented residents.
Computers. relating to, using, or noting an indirect access point into a network, computer, or program: Hackers used a Trojan horse to establish backdoor access to the mainframe.
An entry at the rear of a building, as in Deliveries are supposed to be made at the back door only. [First half of 1500s]
2
A clandestine, unauthorized, or illegal way of operating. For example, Salesmen are constantly trying to push their products by offering special gifts through the back door. This term alludes to the fact that the back door cannot be seen from the front. [Late 1500s]