Word.ws English Dictionary

captcha

/ˈkæp.t͡ʃə/

captcha is the alternative letter-case form of CAPTCHA.

Noun (1) capitalized: CAPTCHA

CAPTCHA (plural CAPTCHAs)

  1. (Internet) A computerized test requiring the human user to perform a task deemed to be difficult to automate, such as entering a displayed series of distorted characters or describing images, to demonstrate that they are a human and not a computer program.
    • CAPTCHA puzzles are intended to be easy for a human to solve but difficult for a computer. Because of the monetary value to spammers of circumventing these controls, an arms race has occurred in which typical CAPTCHA puzzles have […]2011, Dafydd Stuttard, Marcus Pinto, The Web Application Hacker's Handbook: Finding and Exploiting Security Flaws, John Wiley & Sons, →ISBN
    • A CAPTCHA is a quick check to make sure that an actual person, rather than a computer program, is using the website. Web applications use CAPTCHA […]2014, Laura Fitton, Anum Hussain, Brittany Leaning, Twitter For Dummies, John Wiley & Sons, →ISBN, page 24

Noun (2) capitalized: Captcha

Captcha (plural Captchas)

  1. Alternative letter-case form of CAPTCHA.

Forms of captcha

pluralcaptchas
pluralCAPTCHAs
alternative formcaptcha
alternative formCaptcha
pluralCaptchas

Origin of captcha

Coined by a team of researchers at Carnegie Mellon University in 2000 as a loose acronym of “completely automated public Turing test to tell computers and humans apart”.

Words formed from captcha

Questions about captcha

What does captcha mean?
Captcha means a computerized test requiring the human user to perform a task deemed to be difficult to automate, such as entering a displayed series of distorted characters or describing images, to demonstrate that they are a human and not a computer program.
What is captcha the alternative letter-case form of?
Captcha is the alternative letter-case form of CAPTCHA.
What part of speech is captcha?
Captcha is a noun.
How do you pronounce captcha?
Captcha is pronounced /ˈkæp.t͡ʃə/.
What is the plural of captcha?
The plural of captcha is captchas.

Words near captcha in the dictionary

  1. captatives
  2. captayne
  3. captaynes
  4. captayneship
  5. captayneships
  6. captcha
  7. captchas
  8. captee
  9. captees
  10. capthepsin
  11. capting

Source and license

Adapted from Wiktionary: captcha (page history and authors); CAPTCHA (page history and authors); Captcha (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

Last updated:

Cite this entry: “captcha.” Word.ws, https://word.ws/captcha. Based on Wiktionary, CC BY-SA 4.0.