The most common and most likely answer to this crossword clue is the 9 letter word GALLOPING
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More clues leading to the result GALLOPING
- Go send electronic message about everyone making fast progress
- Whupping good, replacing starter, moving fast
- Girl taking long strides, moving fast
- It’s exasperating getting hold of operator when flying
- Georgia election, in retrospect, basically impacts new government’s running
- Young lady running easily and running fast
Buddy explains!

The straight part
We know that "running fast" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case running fast = galloping.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 GALLOPING mean?
GALLOPING verb- (of a horse, etc) To run at a gallop.
- To ride at a galloping pace.
- To cause to gallop.
- To make electrical or other utility lines sway and/or move up and down violently, usually due to a combination of high winds and ice accrual on the lines.
- To run very fast.
- To go rapidly or carelessly, as in making a hasty examination.
- (of an infection, especially pneumonia) To progress rapidly through the body.
- Movement at a gallop.