A clever sort of angle (5)
I believe the answer is:
acute
'sort of angle' is the definition.
'a clever' is the wordplay.
'clever' becomes 'cute' (I've seen this in another clue).
'a'+'cute'='ACUTE'
(Other definitions for acute that I've seen before include "Urgently pressing" , "not seen in cafe here!" , "Perspicacious" , "Sharp as of mind - or pain" , "Very perceptive, having sharp mind" .)