The Japanese spear is commonly known as a "yari." The term "yari" translates to "spear" or "pike" in English. The yari is a polearm weapon that played a significant role in the martial history of Japan.

The yari typically consists of a straight, blade-like spearhead attached to a long shaft made of wood or bamboo. The length of the yari shaft varied, but it was usually around 2 to 4 meters (6 to 13 feet) long, allowing for extended reach in combat.

Yari were widely used by samurai and other warriors in feudal Japan. They were versatile weapons effective in both infantry and cavalry combat. The yari allowed warriors to engage opponents at a distance while also being capable of thrusting, slashing, or even throwing techniques.

Different variations of the yari existed, each designed for specific combat situations. For example:

1. Jumonji Yari: This type of yari had a cross-shaped blade, resembling a double-edged spearhead. The cross shape provided additional cutting edges and increased the weapon's versatility.
2. Naginata Yari: The naginata yari featured a longer shaft with a curved blade, similar to the blade of the naginata polearm. It combined the attributes of a spear and a polearm into a single weapon.
3. Sankaku Yari: Sankaku means "triangular" in Japanese, and the sankaku yari had a triangular-shaped spearhead. This design allowed for increased penetration and effectiveness against armor.

The yari remained in use throughout Japan's feudal era and saw combat on various battlefields. However, with the advent of firearms and changing warfare tactics, the yari's prominence as a primary weapon declined. Nonetheless, it retains its historical and cultural significance and continues to be appreciated as a symbol of Japan's martial heritage.