1 : the pieces that are left after something has been destroyed
After the earthquake, rescuers began digging through the debris in search of survivors.
Everything was covered by dust and debris.
— sometimes used figuratively
She sifted through the debris of her broken marriage.
2 : things (such as broken pieces and old objects) that are lying where they fell or that have been left somewhere because they are not wanted
The crew cleaned up cigarette butts and other debris. [=trash, rubbish]