The most common and most likely answer to this crossword clue is the 9 letter word GALLANTRY
G
A
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More clues leading to the result GALLANTRY
- Courage of everyone imprisoned in tower
- Courage of everyone in supporting construction
- Bravery of girl soldier captured in Lowell’s opening lines
- Spirit of adventure is everything in bridge
- Annoy worker on the railway showing spirit
- Good colleague accepts worker with right spirit
- Bravery of everyone locked in tower
- Bravery from support structure protecting everybody
- Everything a crane has, an admirer has
- The spirit shown by a couple of novices in bridge-like framework
Buddy explains!

The straight part
We know that "bit of mettle" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case bit of mettle = gallantry.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 GALLANTRY mean?
GALLANTRY noun- Courage
- Chivalrous courtliness, especially towards women
- An instance of gallant behaviour or speech