black hat
nounEtymology From the black hats traditionally worn by men in Haredi communities.
1
A Haredi Jew; a member of an ultra-Orthodox Jewish community.
black hat
nounEtymology From the black stetsons (cowboy hats) traditionally worn by such villains.
1
Idiomatic A villain in a story, especially in a Western (a film or other work of the Western genre).
2
Computing, Engineering, Mathematics, Natural sciences, Physical sciences, Sciences Slang A malicious hacker, one who violates computer security out of malice or for personal gain.
Computer security