The most common and most likely answer to this crossword clue is the 9 letter word PROPELLER
I've seen this crossword clue in The Guardian
P
R
O
P
E
L
L
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R
More clues leading to the result PROPELLER
- Support magazine with right driving mechanism
- For Penn and Teller, according to Carroll, it’s a driving mechanism
- Variable length, once absorbed in respectable screw
- Fitting broken by learner with large end of machine screw
- Jack’s screwdriver?
- Driving mechanism to sustain vendors with no restrictions
- ‘Orrible situation being imprisoned by strict screw
- Turner Kelly’s heart stopped? Correct...
- . In favour of bee entrant having no second driving force
- Part of a plane right outside wing
Buddy explains!

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 PROPELLER mean?
PROPELLER noun- One who, or that which, propels.
- A mechanical device with evenly-shaped blades that turn on a shaft to push against air or water, especially one used to propel an aircraft or boat.
- A steamboat thus propelled; a screw steamer.
- A spinnerbait.