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backdoor

American  
[bak-dawr] / ˈbækˈdɔr /

noun

  1. 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.

  2. a secret, furtive, or illicit manner or means.

    The business has a backdoor through which the board of directors can access slush fund money.

  3. an indirect manner or means.

    Marriage counseling was a kind of backdoor into therapy, where I finally faced my dysfunctional relationship with my mother.

  4. 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.

  5. Slang: Usually Vulgar. anus.


adjective

  1. secret; furtive; illicit.

    Special interests pushed through a backdoor contract before the bidding period had expired.

  2. indirect.

    The immigration reform bill included backdoor amnesty for employed undocumented residents.

  3. 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.

  4. Slang: Vulgar. anal.

Etymology

Origin of backdoor

First recorded in 1520–30; back 1 ( def. ) + door

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“Loyalty programs have really become backdoor laboratories for pricing,” she told the Post.

From Salon • May 18, 2026

Pertento Partners founder Eduardo Marques sees a backdoor entry through Korea’s conglomerate holding companies.

From Barron's • May 15, 2026

Courts can no longer use unaffordable bail as a backdoor detention order.

From Los Angeles Times • May 6, 2026

“If it’s really important they’ll leave a message,” said Pahouja, who also runs a Facebook group where more than 26,000 dentists swap tips for maximizing practice profits and using backdoor Roth IRAs.

From The Wall Street Journal • Mar. 26, 2026

I turned away and went to the backdoor where Jeff was waiting.

From "Firegirl" by Tony Abbott

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