Reading comprehension test?

• Challenge for a web user
• Personal check?
• Weapon against automated enemies
• Letters you see to be typed, for example S-K-I-P T-E-A
• Test to keep out bots
• Modern screen test
• Challenge to prove you're human
• Test for screening out bots

Wiktionary Word definitions in Wiktionary
n. 1 A CAPTCHA is a human response test that requires you to enter a series of letters and/or numbers and/or symbols correctly to prove you are a human and not a computer program attempting to spam the site. 2 (context by extension English) Anything that ...