CAPTCHA

American  

[kap-chuh] / ˈkæp tʃə /

Or captcha

noun

Digital Technology.

1. an online test designed so that humans but not computers are able to pass it, used as a security measure and usually involving a visual-perception task.

   Site visitors must solve the “distorted text” CAPTCHA before posting comments.

2. a computer program that generates such tests.

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Etymology

Origin of CAPTCHA

First recorded in 2000–05; C(ompletely) A(utomated) P(ublic) T(uring) (Test to Tell) C(omputers and) H(umans) A(part); inspired by capture ( def. )

Example Sentences

That’s great, and I want that, but sometimes I want entertainment, style and originality too, and all of those things exist in this exciting, economical tale of a woman who can’t get past a CAPTCHA.

From Salon • Feb. 28, 2025

Co-founded by the guy who created CAPTCHA, the app is still hooking aspiring language learners with its welcoming interface, with its unabashedly addictive features, and most importantly by being free.

From Slate • Jul. 25, 2023

This is sort of like — it’s occurring to me that we basically designed a CAPTCHA.

From New York Times • Mar. 20, 2023

Platforms pay people in places mostly outside of the US to label that content; it’s often low-wage and repetitive, and it’s the same kind of work that you do every time you complete a CAPTCHA.

From The Verge • Jan. 30, 2019

Indeed, Luis von Ahn, one of the Carnegie Mellon University team that coined the term CAPTCHA, says he’s skeptical.

From Forbes • Oct. 28, 2013