The term 'Tooth BACK' is a combination of two words, 'MOLAR' and 'BACK'. MOLAR refers to the large, flat-topped teeth located at the BACK of the mouth, which are used for grinding food. They are the last teeth to erupt in the mouth and are the most durable of all the teeth. The term 'BACK' refers to the area behind the molars, which is where the roots of the teeth are located. Together, the term 'Tooth BACK' refers to the area behind the molars, which is where the roots of the teeth are located.