Pugio: This was the most common sidearm carried by Roman soldiers. It was a short, double-edged sword with a thick blade, usually around 15-20 inches long. The pugio was primarily a stabbing weapon, but could also be used for slashing.
Sica: This was a curved, single-edged dagger used by gladiators and some auxiliary units. It was a bit shorter than the pugio and could be used for thrusting and slashing.
Gladius: While not strictly a dagger, the gladius was sometimes used as one. It was a short sword with a double-edged blade, typically 20-24 inches long. Gladiators often used their gladius as a dagger in close combat.
It's important to note that daggers weren't as prevalent in Roman warfare as they are in modern fiction. Roman soldiers relied primarily on their swords and spears for combat.
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