Litscape Default Censored Word List:
24 words ending with th, 11 letters long

aftergrowth chainlength cheesecloth coppersmith cottonmouth decillionth downtoearth gazillionth hairbreadth handbreadth houndsteeth houndstooth nonillionth saddlecloth seventeenth silversmith sixtyeighth sixtyfourth supersmooth thenceforth trilliardth twentyfifth ultrasmooth undergrowth