Allude to an unnoticeable turnaround (5)
I believe the answer is:
refer
'allude' is the definition.
(I've seen this before)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for refer that I've seen before include "Fail (an exam candidate)" , "Pass" , "Make allusion, direct attention with words" , "Draw attention" , "Advert, cite" .)