"Serious bodily injury", bodily injury that results in a permanent disfigurement, loss or impairment of a bodily function, limb or organ or creates a substantial risk of death.
"Strangulation", the intentional interference of the normal breathing or circulation of blood by applying substantial pressure on the throat or neck of another.
"Suffocation", the intentional interference of the normal breathing or circulation of blood by blocking the nose or mouth of another.
Mass. Gen. Laws ch. 265, § 15D