Only two-thirds of cutlery put back, oh dear (4)
I believe the answer is:
oops
'oh dear' is the definition.
(both are said in recognition of a mistake)
'only two-thirds of cutlery put back' is the wordplay.
I cannot quite understand how this works, but
'of' could be 'o' and 'o' is present in the answer.
The remaining letters 'ops' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for oops that I've seen before include "Exclamation on making obvious mistake" , "Clumsy me!" , "My bad" , "- - -a-daisy" , "Blunder explanation" .)