The most common and most likely answer to this crossword clue is the 9 letter word MOTORBIKE
I've seen this crossword clue in The Times
M
O
T
O
R
B
I
K
E
Buddy explains!

The straight part
We know that "Vehicle" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case vehicle = motorbike.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 MOTORBIKE mean?
MOTORBIKE noun- A motorcycle.
- A small and light motorcycle.
- To ride a motorbike; to travel by motorbike.