Dark Land, also referred to as Dark Country is a mysterious continent south of Middle-earth. No Elves or dwarves live here, but there could be wild Men here. The Númenóreans probably visited it on their long journeys, although it is not known if they established dwellings there.
Before Africa was visited by people from Europe, it was known as the "Dark Land". It is possible that Tolkien could have been inspired by this.
In the game Middle Earth Role Play by Iron Crown Enterprises, a Sindarin name for the Dark Land — Morenor (probably intended to mean "Dark Middle-earth") — was given, although it does not appear in any of Tolkien's writings. If the name existed in Sindarin at all the form would more likely be Morennor.