white hat


Definition of white hat

1 : one who is admirable and honorable
2 : a mark or symbol of goodness could use a few more guys in white hats— Robert Christgau
3 : a hacker who tests computer systems for possible vulnerabilities so that they can be fixed Chu, 33, is part of a fraternity known as "penetration testers" or "ethical hackers," a group of experts who are hired to hack into computer systems or find other ways to gain access. These so-called "white hats" will spend days or weeks searching company systems to come up with recommendations for fortifying corporations against such threats.— Greg Wiles — compare black hat

First Known Use of white hat

1965, in the meaning defined at sense 1

History and Etymology for white hat

from the white hats stereotypically worn by law-abiding characters in movie westerns

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Time Traveler for white hat

The first known use of white hat was in 1965

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Rhyming Dictionary: Words that rhyme with white hat

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What made you want to look up white hat? Please tell us where you read or heard it (including the quote, if possible).


authorized for issue (as a bond)

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