This plugin can add rel=”noindex,nofollow” to archive, tag, and category links. You can configure exactly which links are given which attributes. For instance, you could add rel=”noindex,nofollow” to all of your tag links, rel=”noindex” to all of your archive links, and nothing to your category links.

Noindex/Nofollow links

This plugin can add rel="noindex,nofollow" to archive, tag, and category links. You can configure exactly which links are given which attrib …

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This simple and lightweight plugin adds a “Hide from search engines” checkbox above the publish box to pages. By 
ticking this box, a meta tag will be placed into the <code><head></code> section of your page specifying that robots should 
not index the page.
By default this only applies to pages. You may extend this functionality to posts or other custom post types with a small bit of code. See the FAQ’s tab for further instructions.

Noindex Pages

Ask search engines not to index individual pages by checking an option in the publish post box.

Noindex/Nofollow links vs Noindex Pages