Regularly scans in tax returns after electronic systems essentially died out (7)
I believe the answer is:
extinct
'died out' is the definition.
(I've seen this before)
'regularly scans in tax returns after electronic systems essentially' is the wordplay.
'regularly' means one should take alternating letters (regularly take one letter, leave next etc.).
'returns' says the letters should be written in reverse.
'after' is a charade indicator (letters next to each other).
'electronic' becomes 'e' (as in e-mail or e-books).
'systems essentially' becomes 't' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'scans'+'in'+'tax'='scansintax'
The alternating letters of 'scansintax' are 'cnitx'.
'cnitx' reversed gives 'xtinc'.
'xtinc' after 'e' is 'extinc'.
'extinc'+'t'='EXTINCT'
Can you help me to learn more?
(Other definitions for extinct that I've seen before include "(Of species) no longer living" , "Having died out, perished" , "No longer around" , "gone for ever" , "gone forever" .)