The most common and most likely answer to this crossword clue is the 5 plus 5 letter word GREEN BERET
I've seen this crossword clue in The Guardian
G
R
E
E
N
B
E
R
E
T
More clues leading to the result GREEN BERET
- Commando's salute, welcoming new battalion leader previously
- Commando short of experience joining engineers in punt
- Commando not prepared to risk protecting monarch
- Young Bertie, lacking initiative at the outset, surprisingly becomes a soldier
- New sleeping-place mostly occupied by English commando
- Commando, incompletely prepared, has to take a risk protecting monarch
- Commando’s info leads to wager
- Live under shade, even priest belongs to a special unit
Buddy explains!
The straight part
We know that "Commando" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case commando = green beret.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.