A partisan is a type of polearm

Pole weapon

A pole weapon or polearm is a close combat weapon in which the main fighting part of the weapon is placed on the end of a long shaft, typically of wood, thereby extending the user's effective range. Spears, glaives, poleaxes, halberds, and bardiches are all varieties of polearms...

 that was used in Europe during the middle ages. It consisted of a spearhead mounted on a long shaft (usually made of wood) with protrusions on the sides which aided the user in parrying sword thrusts. Like the halberd

Halberd

A halberd is a two-handed pole weapon that came to prominent use during the 14th and 15th centuries. Possibly the word halberd comes from the German words Halm , and Barte - in modern-day German, the weapon is called Hellebarde. The halberd consists of an axe blade topped with a spike mounted on...

 it quickly became obsolete with the arrival of practical firearms although it stayed in use for many years as a ceremonial weapon. In profile, the head of a partisan may look similar to that of a ranseur

Ranseur

A ranseur was a type of polearm used across Europe up to the 15th century. It was still seen in court as a ceremonial weapon through the 17th century...

, ox tongue, or spetum

Spetum

A spetum was a pole weapon of Europe during the 13th century. It consisted of a long pole some 6-8 feet long which was mounted with a spear head with two projections at its base. Many variations of this design flourished over time; some feel that the ranseur is a variation of the spetum...

.