master key


Definition of master key

: a key designed to open several different locks

Examples of master key in a Sentence

Recent Examples on the Web

Vingcard's system encodes a unique cryptographic key into each keycard—and another into every hotel's master keys—that are all designed to be unguessable. Andy Greenberg, WIRED, "A One-Minute Attack Let Hackers Spoof Hotel Master Keys," 25 Apr. 2018 Similarly, hotel rooms around the world are vulnerable to a hack that lets an intruder mimic a hotel's master key and open any door. Brian Barrett, WIRED, "Security News This Week: The Biggest DDoS For Hire Site Goes Down," 28 Apr. 2018 The document would prove to be his master key to building a new life. Kyle Swenson,, "Indiana man missing for decades before being found in Florida thanks to ancestry website now owes abandoned family nearly $2 million," 31 May 2018 According to the researchers, whose claims were earlier reported on by Gizmodo, the software running on those keys, called Vision, has a vulnerability that allows criminals to create master keys and open any door in the facility. Don Reisinger, Fortune, "Millions of Hotel Rooms Are at Risk of 'Master Key' Hack," 25 Apr. 2018 Then rooms are accessed with a master key, Kelly said. Libby Solomon,, "Renovations at Aigburth Vale, a seniors housing complex in Towson, nearly complete," 26 Apr. 2018 In most cases, according to the security researchers, about 20 key combinations are required before the code is determined and the master key is created for the hotel. Don Reisinger, Fortune, "Millions of Hotel Rooms Are at Risk of 'Master Key' Hack," 25 Apr. 2018 One of the keys was an arrow master key that opened postal boxes on Palmerson Drive, Diablo Drive, Dieppe Way, Shade Tree Way, Keoncrest Circle, Porto Pino Way, Golden Vista Way, Burnbray Place and Copper Cove Place, the complaint says. Sam Stanton, sacbee, "‘Dude, I have a magical key for all mailboxes.’ Missing some mail? Better read this | The Sacramento Bee," 6 Apr. 2018 Cops also reviewed the hotel’s key lock system and saw that a master key was used to enter the couple’s room. Madeleine Marr, miamiherald, "They left their hotel room for the day. When they returned, their cash was gone.," 31 Jan. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'master key.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of master key

1577, in the meaning defined above

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Last Updated

9 Mar 2019

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Time Traveler for master key

The first known use of master key was in 1577

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More Definitions for master key

master key


English Language Learners Definition of master key

: a key that can be used to open many locks (such as all the door locks in a building)

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Rhyming Dictionary: Words that rhyme with master key

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