Nest

A Nest is a kind of dungeon in Dragon Nest and most likely the reason the game is called that.

Nests are difficult dungeons that usually make up the "endgame" at the time in game development their respective level was the cap. For instance, Minotaur Nest, the first Nest, was the endgame dungeon when the level cap was somewhere around 24. Because of this, the creation of new Nests is linked to increases in the level cap.

Abyss
Unlike other dungeons, Nests default to Abyss as their "easy" difficulty, and as such behave a little differently than other Abyss dungeons:
 * There is no Abyssal fog / mist / darkness effect.
 * The boss will not be duplicated. Instead, he will simply be extremely powerful.
 * There is no Dimensional Rabbit.
 * Some have a limit on how often one may revive, regardless of how many Life Stones/Resurrection Scrolls they have.

Practice Mode
Similar to Abyss, but without chests and rewards. There is also no revive limit.

Hell & Hardcore
Nests are the only dungeons with higher difficulty settings than Abyss. Depending on the Nest, this may be called either Hell or Hardcore.

It is basically absurdly difficult and even parties who have little to no trouble with Abyss can easily be wiped while playing it.

Solo
This is set to Easy, and has a similar difficulty to regular Normal dungeons. Omits the hell pass and has considerably diminished rewards.