The most common and most likely answer to this crossword clue is the 8 letter word HURTLING
I've seen this crossword clue in Independent
H
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More clues leading to the result HURTLING
Buddy explains!
The straight part
We know that "Belting" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case belting = hurtling.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 HURTLING mean?
HURTLING verb- To move rapidly, violently, or without control.
- To meet with violence or shock; to clash; to jostle.
- To make a threatening sound, like the clash of arms; to make a sound as of confused clashing or confusion; to resound.
- To hurl or fling; to throw hard or violently.
- To push; to jostle; to hurl.
- The act of something being hurtled or thrown.