The most common and most likely answer to this crossword clue is the 2 plus 3 plus 3 letter word BY THE WAY
B
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H
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More clues leading to the result BY THE WAY
- Article found in minor road in passing
- Location of pavement, incidentally
- Where to find hedgerow, incidentally
- Where road signs are often visible, incidentally
- Incidentally, this is where police cameras usually are
- Where to spot a milestone, incidentally
- Where to find pavement artist’s work, incidentally
- Including hard bits means getting aside from the main subject
Buddy explains!

The straight part
We know that "in passing" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case in passing = by the way.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.