The most common and most likely answer to this crossword clue is the 11 letter word CARRIAGEWAY
I've seen this crossword clue in The Daily Telegraph
C
A
R
R
I
A
G
E
W
A
Y
Buddy explains!

The straight part
We know that "road" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case road = carriageway.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 CARRIAGEWAY mean?
CARRIAGEWAY noun- The part of a road that carries traffic.