Pub brawl after Welsh emptied fish cart (11)
I believe the answer is:
wheelbarrow
'cart' is the definition.
(wheelbarrow is a kind of cart)
'pub brawl after welsh emptied fish' is the wordplay.
'pub' becomes 'bar' (both are drinking establishments).
'brawl' becomes 'row' (I've seen this in another clue).
'after' is a charade indicator (letters next to each other).
'welsh emptied fish' becomes 'wheel' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'bar'+'row'='barrow'
'barrow' after 'wheel' is 'WHEELBARROW'.
Can you help me to learn more?
(Other definitions for wheelbarrow that I've seen before include "Gardener's carrier" , "Type of handcart" , "Gardening equipment" , "Small cart" , "Garden cart" .)