The most common and most likely answer to this crossword clue is the 7 letter word RAILWAY
R
A
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More clues leading to the result RAILWAY
- Transport company complain bitterly over route
- Track liar shown up over method
- Public transport: complain bitterly on air
- Revile women having vacated assembly line
- Means of transport – yawl
- Guard with a year to create a transport system
- Lines of communication?
- Disperse warily over area that has lots of tracks
- Warily, a criminal makes tracks
- Company hoping everything keeps on track
Buddy explains!

The straight part
We know that "a transport system" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case a transport system = railway.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 RAILWAY mean?
RAILWAY noun- A transport system using rails used to move passengers or goods.
- A track, consisting of parallel rails, over which wheeled vehicles such as trains may travel.