nether region

At this instant old Roger Chillingworth thrust himself through the crowd—or, perhaps, so dark, disturbed, and evil was his look, he rose up out of some nether region.

But the steward of those nether regions marked him, by the electric lamps, as a lurking passenger to be watched; and wondered who, at that depth in the ship, could be carrying valuables.

The rash of celebrities flashing their nether regions worries Peter Post, director of the Emily Post Institute of etiquette and manners.