English
grimdark
From grim (adjective) + dark (adjective), inspired by the tagline of the tabletop strategy game Warhammer 40,000 (its rulebook first published in September 1987): In the grim darkness of the far future, there is only war.
Today it means
adj Of a film, television programme, video game, written work, etc.: having a gloomy, dystopian atmosphere.
Language periods are conventional ranges, not dates for this word.
Etymograph / grimdark