Catastrophic; appalling (6)
I believe the answer is:
tragic
I believe this is a double definition.
'catastrophic' is the first definition.
(thesaurus)
'appalling' is the second definition.
(tragic can mean horrible or appalling)
(Other definitions for tragic that I've seen before include "Greatly distressing" , "Dreadful" , "Unfortunate" , "Exceedingly sad" , "Calamitous, very sad" .)