The most common and most likely answer to this crossword clue is the 9 letter word ORANGEMAN
I've seen this crossword clue in The Times
O
R
A
N
G
E
M
A
N
More clues leading to the result ORANGEMAN
- Protestant chap addicted to sunbeds?
- One to march or stroll with old woman, breaking leg
- Unionist line adopted by Arab nation
- One to march or stroll about in old crown dependency
- Round kitchen equipment guy who may well be on the march
- Ring kitchen equipment bloke who’s a staunch Protestant
- Freedom of movement in ME country for one used to marching?
- Protestant to roam in Arabian state
- Protestant marching from mountains in state
- Is Ex-President Trump one involved in Irish politics?
Buddy explains!
The straight part
We know that "One to march" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case one to march = orangeman.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.