Rings husband's dropped - how clumsy! (4)
I believe the answer is:
oops
'dropped how clumsy' is the definition.
I can't tell whether this defines the answer.
'rings husband's' is the wordplay.
'rings' becomes 'oo' (multiple circles).
'husband's' becomes 'ps' (I can't justify this - if you can you should give a lot more credence to this answer).
'oo'+'ps'='OOPS'
Can you help me to learn more?
(Other definitions for oops that I've seen before include "Apologetic exclamation" , "My bad" , "The sound of stupidity" , "Oh dear, that's a mistake!" , "Exclamation on making obvious mistake" .)