black hat

[ blak hat ]
/ ˈblæk ˈhæt /
Informal.

noun

a villain, as in a cowboy movie; bad guy.
Digital Technology. a hacker who violates the security of a system without the knowledge or consent of the owner or developer, as for personal profit or for the gratification of causing damage.

Idioms

    wear/put on a black hat, to behave villainously.
Compare white hat.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for black hat

black hat


noun

informal
  1. a computer hacker who carries out illegal malicious hacking work
  2. (as modifier)black-hat hackers Compare white hat
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012