Terrible cart crash involved soldier (6)
I believe the answer is:
tragic
'terrible' is the definition.
(tragic can mean terrible or sad)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for tragic that I've seen before include "heartbreaking" , "Deeply distressing" , "Exceedingly sad" , "Pitiable" , "Mournful" .)