The odds of Boris never making a U-turn? (5)
I believe the answer is:
evens
'the odds' is the definition.
(I've seen this before)
'of boris never making a u-turn?' is the wordplay.
'of' says the answer is hidden in the clue.
'a u-turn?' is a reversal indicator.
'sneve' is hidden in the letters of 'boris never making'.
'sneve' reversed gives 'EVENS'.
(Other definitions for evens that I've seen before include "Bookies' odds matching the amount staked" , "Likelihood" , "Half a chance" , "Level betting" , "Makes equal" .)