Sharp enough to cut keys out (5)
I believe the answer is:
acute
'sharp' is the definition.
(I know that sharp can be written as acute)
'enough to cut keys out' is the wordplay.
I cannot quite see how this works, but
'to cut' could be 'cut' and 'cut' is present in the answer.
The remaining letters 'ae' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for acute that I've seen before include "Keen, good or sharp, senses say" , "Keen; severe" , "not seen in cafe here!" , "Canny" , "Shrewd; severe" .)