SyndicationBlock is an AdBlock filter list to block content syndicators.
Content syndicators are web services which manage paid placements of "related articles" links across a network of many web sites. Content syndication blocks on web pages are often identifiable by taglines such as "around the web", "recommended for you", or "elsewhere on (site name)". The links placed by these services are usually tangentially related to the articles that they are placed on, if at all, and often link to very low quality "clickbait" content (or, even, just to marketing pitches).
Some of the major content syndicators targeted by this blocklist are Taboola and Outbrain.