CAPTCHA

or cap·tcha

[ kap-chuh ]

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.

Word History and Origins

Origin of CAPTCHA¹

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

In the short term, Tools for Humanity plans to generate revenue by offering its iris-based system as an alternative to security technologies like CAPTCHA, the photographic test that is used to sort humans from spam accounts.

From New York Times

The testers found that the system could potentially hire a human to defeat an online Captcha test, lying that it was a person with a visual impairment.

From New York Times

Researchers recently showed that one system was able to hire a human online to defeat a Captcha test.

From New York Times

The group found that the system was able to hire a human online to defeat a Captcha test.

From New York Times

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

From New York Times