Here's a relatively recent example of it being used in US headline writing to mean an explanatory pamphlet - "Republicans to Distribute Shutdown Explainer" ht

Here's a relatively recent example of it being used in US headline writing to mean an explanatory pamphlet - "Republicans to Distribute Shutdown Explainer" http://www.rollcall.com/news/republicans_to_distribute_shutdown_explainer-204600-1.html http://www.rollcall.com/news/republicans_to_distribute_shutd... And here's another from The Washington Post, to mean the text of the article - "Who is Daft Punk? A quick explainer for confused Grammy-watchers" http://www.washingtonpost.com/blogs/style-blog/wp/2014/01/27/who-is-daft-punk-a-quick-explainer-for-confused-grammy-watchers/ http://www.washingtonpost.com/blogs/style-blog/wp/2014/01/27...