The most common and most likely answer to this crossword clue is the 9 letter word VIBRATION
V
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B
R
A
T
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O
N
More clues leading to the result VIBRATION
- One helping to nurse bishop with very fast pulse?
- Bishop and Rat Pack 7 with touching resonance
- Having broached French wine, wobbling a bit or shaking
- Trembling, very irritated at first, unruly child upset naval lieutenant?
- Trembling with emotional feeling
- Back and forth motion of an orbit, one very peculiar
- Very independent bishop to restrict back and forth movement
Buddy explains!

The straight part
We know that "Back and forth motion" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case back and forth motion = vibration.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 VIBRATION mean?
VIBRATION noun- The act of vibrating or the condition of being vibrated.
- Any periodic process, especially a rapid linear motion of a body about an equilibrium position.
- A single complete vibrating motion.
- An instinctively sensed emotional aura or atmosphere; vibes.