Old English tord "piece of excrement," from Proto-Germanic *turdam (source also of Middle Dutch torde "piece of excrement," Old Norse tord-yfill, Dutch tort-wevel "dung beetle"), from PIE *drtom, past participle of root *der- "to split, flay, peel;" thus "that which is separated ("torn off") from the body" (compare shit (v.) from root meaning "to split;" Greek skatos from root meaning "to cut off; see scatology). As a type of something worthless and vile, it is attested from mid-13c. Meaning "despicable person" is recorded from mid-15c.
A tord ne yeue ic for eu alle ["The Owl and the Nightingale," c. 1250]
Alle thingis ... I deme as toordis, that I wynne Crist. [Wyclif, Philippians iii.8, 1382; KJV has "I count all things ... but dung, that I may win Christ"]