Meaning of "Underground" by Tom Waits

The lyrics of "Underground" by Tom Waits paint a vivid picture of a hidden world beneath our feet, filled with activity and life that goes unnoticed by most people. The imagery of bones rattling, roots swinging, and trucks unloading suggest a sense of constant movement and industry in this underground realm. The repetition of the phrase "there's a world going on underground" emphasizes the idea that there is an entire existence existing below the surface level that we are not aware of. This can be seen as a metaphor for the hidden aspects of society or human nature that are often overlooked or ignored. The contrast between the bustling underground world and the sleeping world above it highlights the idea that there is always more to discover beneath the surface, both literally and metaphorically.