The most common and most likely answer to this crossword clue is the 8 letter word GAUNTLET
G
A
U
N
T
L
E
T
More clues leading to the result GAUNTLET
- German relative allowed to give punishment
- Surmounting obstacle is skinny runner’s challenge
- Bony obstruction presents a challenge
- Check on spare glove
- Haggard suffered punishment that’s at the hand of knight, eg
- Ageing aunt lethargically embraces challenge
- Allowed to carry thin glove
- Haggard locks each trunk primarily as a means of protection
- Bony obstruction presents challenge
- Some armour Britain lost in dreadful gun battle
Buddy explains!

The straight part
We know that "Part of armour" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case part of armour = gauntlet.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 GAUNTLET mean?
GAUNTLET noun- Protective armor for the hands, formerly thrown down as a challenge to combat.
- A long glove covering the wrist.
- A rope on which hammocks or clothes are hung for drying.
- Two parallel rows of attackers who strike at a criminal as punishment
- Simultaneous attack from two or more sides
- Any challenging, difficult, or painful ordeal, often one performed for atonement or punishment
- A temporary convergence of two parallel railroad tracks allowing passage through a narrow opening in each direction without switching.