Definitions for "De-Listing"
When pages are removed from a search engine's index it is called de-listing.
Also known as banning. The removal of a web page from a search engine or directory's index. Removal can occur as a result of a cleanup of dead links, as a penalty for spamming, or because of server issues at a site's host.
Removal of a Website from a Search Engine's index. Removal can occur because of perceived attempts at ‘spamdexing' (defined below).