Praetorium

The Greek word (praitorion) thus rendered in Mark 15:16 is rendered "common hall" (Matt. 27:27, marg., "governor's house"), "judgment hall," (John 18:28, 33, marg., "Pilate's house", 19:9; Acts 23:35), "palace" (Phil. 1:13). This is properly a military word. It denotes:

1. the general's tent or headquarters
2. the governor's residence, as in Acts 23:35 (R.V., "palace")
3. the praetorian guard (See PALACE), or the camp or quarters of the praetorian cohorts (Acts 28:16), the imperial guards in immediate attendance on the emperor, who was "praetor" or commander-in-chief.