He possibly angers working with it (5,3)
I believe the answer is:
inert gas
'he possibly' is the definition.
(helium - symbol 'He' - is an example)
'angers working with it' is the wordplay.
'working with' indicates an anagram (working with the letters).
'angers' with its letters anagrammed with 'it' gives 'INERT GAS'.
(Other definitions for inert gas that I've seen before include "One expects no reaction from such" , "Eg, helium or argon" , "He perhaps" , "Eg, helium, xenon etc." , "He, amongst others" .)