One wheeled by a boy? (6)
I believe the answer is:
barrow
'one' is the definition.
The definition and answer can be both quantities as well as being singular nouns.
Maybe there's an association between them I don't understand?
'wheeled by a boy?' is the wordplay.
'wheeled' says the letters should be written backwards (letters are wheeled back).
'by a' becomes 'wor' (I can't justify this - if you can you should believe this answer much more).
'boy?' becomes 'Rab'.
'wor'+'rab'='worrab'
'worrab' reversed gives 'BARROW'.
Can you help me to learn more?
(Other definitions for barrow that I've seen before include "Load-carrying cart - burial mound" , "old burial ground" , "Cart for the river?" , "Handcart; burial mound" , "One-wheeled handcart" .)