The most common and most likely answer to this crossword clue is the 8 letter word WEAPONRY
I've seen this crossword clue in The Guardian
W
E
A
P
O
N
R
Y
More clues leading to the result WEAPONRY
- Tailless animal carried in tired arms
- Arsenal player initially performing in tired environment
- Way person, having lost son, waves about arms
- Used ropeway to carry nationalist arms
- Arms tired keeping pressure on
- Arms becoming tired carrying piano leg
- Any power may resort to producing armaments
- Armaments open war clashes before end of July
- Arms tired, having carried piano on
- Tired holding power supported by arms
Buddy explains!

The straight part
We know that "Arms" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case arms = weaponry.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 WEAPONRY mean?
WEAPONRY noun- Weapons, collectively