GeekParadize

<p>Comment Word Blacklist Manager will retrieve a list of blacklist terms from a remote source and update the <code>blacklist_keys</code> setting in WordPress. The list will update itself on a schedule to keep your terms current. Any manually added items will be retained, and an exclusions list is also created if there are terms from the source you want to allow.</p>


Comments Word Blacklist Manager

Remotely add known terms into the WordPress blacklist keys to manage spam

Kat Hagan

<p>This plugin allows you to selectively disable comments for visitors from certain sites (e.g. reddit).  If a visitor’s HTTP referer matches one of the hosts you’ve blacklisted, your post will look as if comments have been disabled (neither existing comments nor the new comment form will be shown).</p>


Disable Comments By Referer

Ban visitors from certain sites from viewing or adding comments.

Comments Word Blacklist Manager vs Disable Comments By Referer