Excellent work flourished in tense environment? (3-6)
I believe the answer is:
top-flight
'excellent' is the definition.
(I've seen this before)
'work flourished in tense environment?' is the wordplay.
I cannot quite see how this works, but
'work' could be 'op' (short for opus) and 'op' is present in the answer.
'flourished' could be 'fl' (abbreviation in biographical entries) and 'fl' is located in the answer.
'tense' could be 'tight' (similar in meaning) and 'tight' is found in the leftover letters.
This accounts for all the letters.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for top-flight that I've seen before include "Excellent -- best possible" , "Of the highest class" , "Superior" , "Highest level" .)