backgrounder
back ground er |ˈbakˌgroundər ˈbækɡraʊndər | ▶noun an official briefing or handout giving background information: their departure had to be explained by aides in a backgrounder the next day.
back |ground ¦er ▶noun N. Amer. an official briefing or handout giving background information.
The Wordsmith Dictionary
The Wordsmith Dictionary