One’s undoing hose at your convenience? (8)
I believe the answer is:
waterloo
'one's undoing' is the definition.
'Waterloo' can be an answer for 'undoing' (I've seen this in another clue). I'm unsure of the 'one's' bit.
'hose at your convenience?' is the wordplay.
I cannot really understand how this works, but
'hose' could be 'water' (hose a flowerbed say) and 'water' is located in the answer.
'convenience?' could be 'loo' (both can mean a toilet) and 'loo' is located in the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for waterloo that I've seen before include "Tracked site" , "Napoleon's 1815 defeat" , "Belgian battle site" , "London rail terminus" , "Total or crushing defeat" .)