Sentence:  Erasmus ascribes the frequent plagues in England to the <WSD>nastiness</WSD> and dirt and slovenly habits among the people. “The floors,” says he, “are commonly of clay, strewed with rushes, under which lies unmolested an ancient collection of beer, grease, fragments, bones, spittle, excrements of dogs and cats, and every thing that is nasty.” 
Meaning of the word marked with <WSD> tags:  Lack of cleanliness.