large regional newspaper; block newspaper
Refers to a newspaper with circulation spanning multiple prefectures, larger than a local paper but not national. Often contrasted with 全国紙 (national newspaper) and 地方紙 (local newspaper).
A block newspaper is a newspaper sold in multiple prefectures.
The Chunichi Shimbun is one of the representative block newspapers.
Compound of ブロック (block, from English) and 紙 (newspaper). The term likely arose from the concept of a regional 'block' of prefectures served by a single newspaper.