An Oriza, or Riza for short is the name given to a number of items within the Dark Tower Series.
Role as a weapon
The main usage of the word Oriza is used for the plate like weapon thrown like a discus to decapitate enemies. They can be made of light metal alloy; their edges decorated with blue webbing and a seedling rice plant. Where the plants cross they form the letters Zn meaning here and now. As they fly through the air, it makes a whistling sound through the inclusion of an item that looks similar to a pencil sharpener attached to the bottom of the plate.
They are thicker at a certain point, often where the Zn lettering is, as the rest of the edges are razor sharp to kill enemies. The Sisters of Oriza are known for their proficiency with these weapons.
The seedling rice plants that decorate the Oriza weapons are also called Orizas.