Increasing in filthiness; living in filthiness.
From Latin insordescent-em, prior participle of insordescere, "to become foul or dirty," from in + sordescere "to become dirty," from sordes, "dirt, filth."
1731 Chandler tr. Limborch's Hist. Inquis. II. iii. xviii. 82:
A Man is said to be insordescent in Excommunication, who, after he hath been by Name declared Excommunicate, persists in that Excommunication for a Year. Ibid., He must be deprived of his Benefice for Insordescence.
A former friend of mine, let's call him M, used to live in such insordescence that I couldn't bring myself to visit his home, and never liked it when he visited mine. His room was filled with dirty crockery and, when they ran out, dirty tins of food. His floor was so covered in dirty clothes, dog and cat leavings and other foul things that he had to point out the places where I could safely step. To this day, my chairs and couch bare the marks where he used to wipe his geasy fingers to keep them clean. True story - M truely lived a life of complete disgust, and likely still does.