Final answer:
Clay that has been fired once to prepare it for glazing is known as bisque or biscuit ware. This initial firing happens at around 900 degrees Celsius and results in a hardened, porous surface that can absorb glaze.
Step-by-step explanation:
Clay that has been fired once, preparing it for glazing, is called bisque or biscuit ware. This refers to pottery that has been fired in a kiln at a lower temperature to harden the clay and make it porous enough to absorb a glaze. The process of creating ceramics involves multiple steps, with the initial firing without glaze helping to substantially harden the piece to avoid damage during the glazing and subsequent higher temperature firing. The initial firing typically occurs at a temperature of about 900 degrees Celsius, which sets the shape of the pottery and ensures the porous surface needed for the glaze to adhere properly during the second firing.