1706, "stoppage of pulse, absence of pulse," from Modern Latin, from Greek asphyxia "stopping of the pulse," from a- "not" (see a-(3)) + sphyzein "to throb." Obsolete in its original sense; the transferred sense of "suffocation" is from 1778, but it is a "curious infelicity of etymology" [OED] because victims of suffocation have a pulse for some time after breathing has stopped.