A dagger is a fighting knife typically with a very sharp point and usually one or two sharp edges, typically designed or capable of being used as a cutting or thrusting weapon. Daggers have been used
The Fairbairn–Sykes fighting knife, a modern-day dagger
A bronze dagger from Lorestan, Iran, 2600–2350 BCE
A Neolithic dagger from the Muséum de Toulouse
Pre-Roman Iberian iron dagger forged between the middle of the 5th and the 3rd century BC
A rondel dagger or roundel dagger is a type of stiff-bladed dagger used in Europe in the late Middle Ages, used by a variety of people from merchants to knights. It was worn at the waist and could be
Dagger
…A wide variety of thrusting knives have been described as daggers, including knives that feature only a single cutting edge, such as the European rondel dagger or the Afghan pesh-kabz, or, in some instances, no cutting edge at all, such as the stiletto of the Renaissance. However, in the last hundred years or…
Close-quarter fighting with rondel daggers from Hans Talhoffer's Fechtbuch. This image is from a manual of combat from 1467. It is one of a series of images of two men fighting hand to hand with rondels, demonstrating possible attacks and defences.
Rondel dagger (Burgundy, c. 1500)
Merchants wearing rondels (uncropped version)
Armoured longsword combatants wearing roundel daggers as backup weapons (plate 214, Codex Wallerstein, 15th century)