Expression of annoyance from celebrity performing U-turn (4)
I believe the answer is:
rats
'expression of annoyance' is the definition.
(mild curse said when annoyed)
'celebrity performing u-turn' is the wordplay.
'celebrity' becomes 'star' (I've seen this before).
'performing u-turn' shows that the letters should be reversed in order (the letters turn around).
'star' in reverse letter order is 'RATS'.
'from' acts as a link.
(Other definitions for rats that I've seen before include "Snoopy's imprecation - vermin" , "Blast" , "Tells" , "Heels" , "were piped away" .)