Container filled with grit, else toxic spirit (11)
I believe the answer is:
poltergeist
'spirit' is the definition.
(I know that poltergeist is a type of Ghost)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for poltergeist that I've seen before include "Disturbing ghost" , "Active ghost" , "Mischievous spirit" , "Noisy ghost" , "Destructive spirit" .)