ABSTRACT
The keyword in the definition of wastewater is “used” or “spent.” That is, the water has been used or spent and now it has become a
waste water
. On the other hand, to become a sewage, it is enough that water becomes polluted whether or not it had been used. When one uses the word wastewater, however, the meaning of the two words is blended such that they now often mean the same thing.
