rathole

noun
High School
1

An entrance to a living area or passageway used by mice or rats.

2

A living area used by mice or rats, or a similar living area used by other animals.

3

A particularly squalid human residence or other place.

4

An area of a silo that has undergone ratholing, so that material moves mostly through the centre and accumulates around the edges.

5

A pigeonhole.