Tense auditor's shown how (4)
I believe the answer is:
taut
'tense' is the definition.
(similar in meaning)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for taut that I've seen before include "Tightly drawn" , "Without slack" , "Fully stretched" , "Stretched, pulled tight" , "On the slope" .)