Obelos | 'Spit'. the long iron point of a pilum or soliferreum javelin. |
Obsidio | Siege. |
Ocrea | Greave. |
Officialis | Member of administrative staff. |
Officium | A - staff.
B - office. |
Officium rationum | Accounting office. |
Oikeios | Organic. incorporated into permanent strucure of a military unit. |
Oiketès | Household retainer. private bodyguard. |
Onager | 'Wild ass'. torsion gun. |
Onagros | 'Wild ass'. torsion gun. |
Opera vacans | Soldier exempt from fatigue duty. first century AD term for the type of soldier called an immunis from the second century AD on. |
Oppidum | Fortified town. |
Oppugnatio | Assault. |
Optimas | A - noble, war lord.
B - Byzantine horse guard. |
Optimates | Byzantine elite cavalry force. |
Optime Maxime, conserva numerus omnium militantium | Best and Greatest, protect the collective of all serving soldiers. motto used on military equipment.. |
Optio | 'Chosen one'.
A - NCO.
B - private with special responsibilities. |
Optio ad spem ordinis | NCO selected for promotion to centurionate. |
Optio candidatus | NCO singled out for promotion to rank of centurio . |
Optio carceris | NCO in charge of the prison cells. |
Optio centuriae | 'Chosen men of the company'. NCO serving as rearrank officer of a centuria, in the imperial army classed as a duplicarius , a NCO on double basic pay. |
Optio centurionis | 'Chosen man of the centurion'. NCO serving as rearrank officer of a centuria. |
Optio equitum | NCO of the legionary or praetorian horsemen. |
Optio fabricae | Soldier or NCO in charge of a work shop. |
Optio navaliorum | NCO or specialist soldier in charge of boats. |
Optio praetorii | Specialist soldier or NCO attached to headquarters. |
Optio principalis | NCO. not all optiones were noncommissioned officers, called principales from the second century on. |
Optio speculatorum | NCO of elite cavalry bodyguards. |
Optio spei | NCO selected for promotion to centurionate. |
Optio statorum | NCO of military constabulary. |
Optio tribuni | Assistant to tribune. |
Optio valetudinarii | Orderly in charge of hospital. |
Optioon | Nco. |
Opus | Work. job. task. |
Ordinarius/Ordinatus | Centurion. |
Ordinatio | A - battle deployment.
B - commissioning as centurio . |
Ordo | A - battle line.
B - military unit.
C - post of centurio . |
Ordo equester | The equestrian order. Originally the class of wealthy citizens from which the cavalry was recruited, later the class from which many senior officers were drawn. |
Origo | Origin. |
Origo castris | 'Born in the camp'. soldier originating from civilian settlement adjacent to an army base. |
Oothismos | The shoving between two phalanges . |
Ouetranos | Veteran. discharged soldier. |
Ouexillatioon | Detachment. provisional unit. Greek term for vexillatio . |
Ornithoboros | 'Bird carrier'. unarmed Byzantine NCO who apparently no longer carried an eagle standard. |
Oulamos | Squadron. cavalry unit. |
Ouragos | Rearrank officer. optio . |
Otium castrorum | Time off-duty. |
Ovatio | Triumphal entry for victorious commander. |
