gray hat

American  

[grey hat] / ˈgreɪ ˈhæt /

noun

Computers Informal.

1. a hacker who violates the security of a system without true malicious intent but often without the prior knowledge or consent of the owner or developer, and who later reports system vulnerabilities to the authorities, sometimes for personal profit.

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Etymology

Origin of gray hat

First recorded in 2000–05; modeled after gray market ( def. )

Example Sentences

I wore a long-sleeved shirt, blue jeans and a gray hat I had purchased the night before.

From Los Angeles Times • Nov. 30, 2025

The photos show Barnette, wearing a winter coat and gray hat, walking behind two Proud Boys members who were later indicted for participating in the Capitol riot.

From Reuters • May 16, 2022

Incoming Timberwolves owner Marc Lore, who's partnering with Alex Rodriguez to buy the club from Glen Taylor, sat courtside in a blue mask and a gray hat and had a blast watching the action.

From Fox News • Oct. 20, 2021

Incoming Timberwolves owner Marc Lore, who’s partnering with Alex Rodriguez to buy the club from Glen Taylor, sat courtside in a blue mask and a gray hat and had a blast watching the action.

From Seattle Times • Oct. 20, 2021

Before he was many days old he was not only looking like a mouse but acting like one, too—wearing a gray hat and carrying a small cane.

From "Stuart Little" by E.B. White