An everyday tax worry (5)
I believe the answer is:
angst
'worry' is the definition.
(I've seen this before)
'an everyday tax' is the wordplay.
'everyday tax' becomes 'gst' (I am not sure about this - if you are sure you should believe this answer much more).
'an'+'gst'='ANGST'
Can you help me to learn more?
(Other definitions for angst that I've seen before include "Nonspecific sense of anxiety" , "Horrible feeling" , "(German) anxiety state" , "Acute anxiety about oneself" , "Painful feeling" .)