What is Asphyxia?

Legal Definition
Asphyxia or asphyxiation is a condition of severely deficient supply of oxygen to the body that arises from abnormal breathing. An example of asphyxia is choking. Asphyxia causes generalized hypoxia, which affects primarily the tissues and organs. There are many circumstances that can induce asphyxia, all of which are characterized by an inability of an individual to acquire sufficient oxygen through breathing for an extended period of time. Asphyxia can cause coma or death.

In 2013 about 1.6 million cases of unintentional suffocation occurred. The word asphyxia is from Ancient Greek α- "without" and σφύξις sphyxis, "squeeze" (throb of heart).
-- Wikipedia
Legal Definition
In medical jurisprudence. A morbid condition of swooning, suffocation or suspended animation, resulting in death if not relieved, produced by any serious interference with normal respiration (as, the inhalation of poisonous gases or too rarified air, choking, drowning, obstruction of the air passages or paralysis of the respiratory muscles) with a censequent deficiency of oxygen in the blood. See State v. Baldwin, 36 Kan. 1, 12 Pac. 328.
-- Black's Law Dictionary
Legal Definition
Suspended animation usually caused by suffocation, drowning or inhalation of gas. See 36 Kan. 1, 12 Pac. 318.
-- Ballentine's Law Dictionary