More exacting than ever (6)
I believe the answer is:
severe
'more exacting' is the definition.
'severe' can be an answer for 'exacting' (thesaurus). I am not certain of the 'more' bit.
'than ever' is the wordplay.
I cannot really understand how this works, but
an anagram of 'ever' is 'vere' which is within the answer.
The remaining letters 'se' is a valid word which might be clued in a way I don't understand.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for severe that I've seen before include "Terrible" , "Austere or strict" , "Very plain in style or appearance" , "Austere, serious" , "Ascetic - demanding - bitter" .)