The most common and most likely answer to this crossword clue is the 6 plus 3 letter word BARROW BOY
I've seen this crossword clue in The Times
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More clues leading to the result BARROW BOY
Buddy explains!
The straight part
We know that "Itinerant trader/youngster in Cumbria?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case itinerant trader/youngster in cumbria? = barrow boy.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 BARROW BOY mean?
BARROW BOY noun- A boy or man who sells goods – especially fruit or vegetables – from a barrow; a costermonger.
- By extension, a financial industry worker from a working class or lower middle class family background.