Answer: dishwater

AnswerCrossword Clue
DISHWATERDullness exemplar
DISHWATERSink filler
DISHWATERIt's dull, it's said
DISHWATERSymbol of dullness, weakness, etc.
DISHWATEREpitome of dullness
dishwaterwater used for washing dishes
dishwaterDirty water in which dishes have been washed