Moving past irritable hosts (5)
I believe the answer is:
astir
'moving' is the definition.
(I've seen this before)
'past irritable hosts' is the wordplay.
'hosts' says the answer is hidden in the clue.
'ASTIR' can be found hidden inside 'past irritable'.
(Other definitions for astir that I've seen before include "Awake and out of bed" , "Out of bed or on the move" , "Excited; out of bed" , "Excitedly moving" , "Starting to move" .)