Is there a way to block a website from showing up in Google, Yahoo and other search engines? How?

[Pinnacle]

[Jake]

That's right, you can't influence the appearance of some competing business's site, but can use robots.txt instructions to not index certain pages of your own site, I suppose you can apply it to all pages.

Safe search settings can exclude certain adult titles appearing on your computers search results.

[James]

you can control the website to not showing in search engines by providing robots.txt file.

[dotspiders]

You can change the text in robot.txt, when you put a condition in robot.txt as no-follow. Then,Google Crawler (or) any other crawlers will not crawl your website.Hope my comment helps you and all the best.