asphyxia

Concise Oxford English Dictionary © 2008 Oxford University Press:
asphyxia /əsˈfɪksɪə/

▶noun a condition arising when the body is deprived of oxygen, causing unconsciousness or death.

– derivatives
asphyxial adjective,
asphyxiant adjective & noun.

– origin C18 (in the sense ‘stopping of the pulse’): mod. L., from Gk asphuxia, from a- ‘without’ + sphuxis ‘pulse’.