The most common and most likely answer to this crossword clue is the 8 letter word DETRITUS
I've seen this crossword clue in Financial Times
D
E
T
R
I
T
U
S
More clues leading to the result DETRITUS
- Car capital? Nothing’s left, just endless rubble
- Debris Oscar removed from Motown, America
- Badly rusted, it becomes rubbish
- Car capital leaves nothing — just endless rubble
- Litter? New duster will collect it
- Editor, on reflection, right to cut biblical book? Rubbish
- Rubbish put out? It rusted
- Top sturdiest construction
- Waste of time to stop in need of rest when climbing 28
- Fragments tire 5 out
Buddy explains!

The straight part
We know that "Waste" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case waste = detritus.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does DETRITUS mean?
DETRITUS noun- (chiefly geological) Pieces of rock broken off by ice, glacier, or erosion.
- Organic waste material from decomposing dead plants or animals.
- Debris or fragments of disintegrated material.