Cockney rings for acknowledgement of error (4)
I believe the answer is:
oops
'cockney rings' is the definition.
('hoops' - 'hoop' can be a synonym of 'ring' - said with the 'H' dropped - a cockney accent.)
'acknowledgement of error' is the wordplay.
I cannot really understand how this works, but
'of' could be 'o' and 'o' is found within the answer.
The remaining letters 'ops' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
'for' is the link.
Can you help me to learn more?
(Other definitions for oops that I've seen before include "Oh dear, I've spilt something!" , "I've made a mistake!" , "Clumsy me!" , "Something's been spilt!" , "Exclamation on making a minor mistake" .)