End user at the opening might turn out to minimise it (10)
I believe the answer is:
understate
'opening might turn out to minimise it' is the definition.
I can't judge whether this defines the answer.
'end user at the' is the wordplay.
I cannot really see how this works, but
an anagram of 'end' is 'nde' which is present in the answer.
'at' is within the answer.
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is found in the answer.
an anagram of 'user' is 'urse' which is located in the left over letters.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for understate that I've seen before include "Play down" , "Represent as less important" , "Speak with restraint" , "Minimise the significance of (something)" , "Downplay" .)