Sentence:  An <WSD>overfired</WSD> biscuit has insufficient porosity for glazing. An <WSD>overfired</WSD> body warps and bloats. An <WSD>overfired</WSD> glaze often blisters by the volatilization of part of its composition. It also reaches a stage where its viscosity is too low to keep it on the pot. 
Meaning of the word marked with <WSD> tags:  Fired at a high (or excessively high) temperature.