From trachelos; to seize by the throat or neck, i.e. To expose the gullet of a victim for killing (generally, to lay bare) -- opened.
see GREEK trachelos
1. to seize and twist the neck or throat; used of combatants who handle thus their antagonists (Philo, Plutarch, Diogenes Laërt, others).
2. to bend back the neck of the victim to be slain, to lay bare or expose by bending back; hence, tropically, to lay bare, uncover, expose: perfect passive participle τετραχηλισμενος τίνι, laid bare, laid open, made manifest to one, Hebrews 4:13.