deadliness

n.

致命；

The deadliness of mass murderers
Low-Poundage Deadliness
On the deadliness of deadlines 
WHO Probes Deadliness of China's Pig-Borne Disease
Spaceflight boosts bacterial deadliness
Case Histories Document Deadliness of C. sordellii
Mass homicide and suicide deadliness and outcome.
Prion deadliness tied to division - The Scientist - Magazine of the Life Sciences
Case histories document deadliness of C. sordellii.(Infectious Diseases)(Disease/Disorder overview)
Deadliness, organisational change and suicide attacks: understanding the assumptions inherent in the use of the term ‘new terrorism’