dirtyoudaoicibaDictYouDict
dirt: [13] Dirt was originally drit, and meant ‘excrement’ (it was borrowed from Old Norse drit, which goes back to a prehistoric Germanic base *drit- that also produced Dutch dreet ‘excrement’). The toned-down sense ‘soiling substance’ is of equal antiquity with ‘excrement’ in English, and the modern English form dirt first appeared in the 15th century, by a process known as metathesis in which two sounds are reversed.
dirt (n.)youdaoicibaDictYouDict
15c. metathesis of Middle English drit, drytt "mud, dirt, dung" (c. 1300), from Old Norse drit, cognate with Old English dritan "to void excrement," from Proto-Germanic *dritan (cognates: Dutch drijten, Old High German trizan). Used abusively of persons from c. 1300. Meaning "gossip" first attested 1926 (in Hemingway); dirt bike is 1960s. Dirt-cheap is from 1821. Dirt road attested by 1852.