Rod and line in cart (6)
I believe the answer is:
barrow
'cart' is the definition.
(barrow is a kind of cart)
'rod and line' is the wordplay.
'rod' becomes 'bar' (I've seen this before).
'and' means one lot of letters go next to another.
'line' becomes 'row' (a row or line of things).
'bar'+'row'='BARROW'
'in' is the link.
(Other definitions for barrow that I've seen before include "Small cart with two wheels, or old burial mound" , "old burial ground" , "Cart; grave mound" , "Cart; tumulus" , "Northern town" .)