Is there any way if we can block bad words from submitting forum thread. I checked with EE's native module Blacklist/White but seems it works if any blacklisted URL (or its part) is being submitted. Could anyone suggest me a solution.
You will want to modify your Word Censoring preferences which will replace bad words with hash marks, e.g. ######.
By default the Discussion Forum plugin does not provide to block bad words. But if you need then, you should customize and add the Admin Approval of newly posted topics type of functionality in the existing discussion forum plugin. It will not shows the latest topics posted by user. The latest topics only shows when Admin approves it.