The most common and most likely answer to this crossword clue is the 9 letter word CLARENCES
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More clues leading to the result CLARENCES
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The straight part
We know that "carriages" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case carriages = clarences.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.
Crossword Answer definitions
CLARENCES noun- A kind of carriage popular in the 19th century; a four-wheeled horse-driven vehicle with a glass front and room for four passengers.