captcha

noun capt·cha \ ˈkap-chə \
variants: or CAPTCHA
|Updated on: 14 May 2018

Definition of captcha

: a test to prevent spamming software from accessing a website by requiring visitors to the site to solve a simple puzzle (typically by reading and transcribing a series of numbers or letters from a distorted image) in order to gain access
  • The point of the CAPTCHA is that reading those swirly letters is something that computers aren't very good at. If you can read them, you're probably not a piece of software run by a spammer.
  • —Lev Grossman

Recent Examples of captcha from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'captcha.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of captcha

Completely Automatic Public Turing test to tell Computers and Humans Apart (with deliberate pun on 1capture)



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