What debts do as a result of multiple collision (4,2)
I believe the answer is:
pile up
'result of multiple collision' is the definition.
Although both the answer and definition are verbs in their base form, I don't see how one could define the other.
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for pile up that I've seen before include "Stack" , "Collision of several cars" , "Multiple car collision" , "Multi-vehicle crash" , "Amass" .)