susparasso describes a forceful bodily seizure that throws a person into violent convulsions.

The attested use depicts a violent bodily seizure: in both accounts, the same aorist active form describes the spirit's action upon the afflicted person, followed by falling or being thrown down.

1. Violently seizing the body · dominant

   In Luke 9:42, συνεσπάραξεν occurs after the demon throws the child down; the APB renders the action as having “convulsed him violently.” In Mark 9:20, the same aorist active indicative form follows the spirit's seeing him, with the APB rendering “convulsed him” before he falls and rolls on the ground.

   Luke 9:42Mark 9:20

In the Anselm Project Bible: The APB presents the action as “convulsed him violently” in Luke 9:42 and “convulsed him” in Mark 9:20. These renderings confirm the scenes' violent bodily action without isolating every nuance of the Greek term.