Force abandoning weapons causes annoyance (5)
I believe the answer is:
riles
'causes annoyance' is the definition.
Although both the answer and definition are verbs in their -s form, I can't see how one could define the other.
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for riles that I've seen before include "Irritates, nettles" , "Annoys in American way" .)