Definitions for "Doorway pages"
A "Black Hat" technique involving the creation of pages no surfer is ever intended to see, for the sole purpose of driving SE traffic to another page. This will usually get you banned.
These are specially created entry pages designed to rank well for a keyword in a search engine's listings and they usually have very little useful content. Most search engines recommend that you do not use doorway pages.
Web pages created specifically for search engine rankings and not for the benefit of visitors.