There are automated filters that monitor the site. They scan the written content, looking for duplicated material or banned subject matter. Certain words can trip the filters and trigger alert messages or block what appears to be something improper.
If you feel a filter tripped in error, you can always contact the moderation team to get a manual review. You can also avoid these sorts of issues by carefully reading the site rules and making sure your content stays away from problem topics and questionable areas.