Perhaps fool's turned anxious (8)
I believe the answer is:
stressed
'anxious' is the definition.
(stressed can mean anxious or uneasy)
'perhaps fool's turned' is the wordplay.
'perhaps fool's' becomes 'dessert's' (fool is a type of dessert).
'turned' is a reversal indicator.
'desserts' backwards is 'STRESSED'.
(Other definitions for stressed that I've seen before include "Strained or emphasised" , "exerted pressure" , "Brought out" , "Emphasised, underlined" , "Flustery" .)