Disregard wreck (5,3)
I believe the answer is:
write off
I believe this is a double definition.
'disregard' is the first definition.
(write off can mean to disregard or dismiss)
'wreck' is the second definition.
(as in writing off a car)
(Other definitions for write off that I've seen before include "cancel a bad debt" , "trash" , "Send away" , "This vehicle cannot be repaired" , "Send a letter - complete failure" .)