harnessyoudaoicibaDictYouDict[harness 词源字典]
harness: [13] Etymologically, harness is ‘equipment for an army’. It comes via Old French herneis ‘military equipment’ from an unrecorded Old Norse *hernest, a compound formed from herr ‘army’ (a descendant of prehistoric Germanic *kharjaz ‘crowd’ and related to English harangue, harbinger, harbour, and harry) and nest ‘provisions’.

English took it over in the general sense ‘equipment’, and did not apply it specifically to the straps, buckles, etc of a horse until the 14th century (it was originally used for any equestrian equipment, including reins, saddles, etc, but now it denotes exclusively the gear of a draught horse).
=> harangue, harbinger, harbour, harry, herald[harness etymology, harness origin, 英语词源]
harness (n.)youdaoicibaDictYouDict
c. 1300, "personal fighting equipment, body armor," also "armor or trappings of a war-horse," from Old French harnois, a noun of broad meaning: "arms, equipment; harness; male genitalia; tackle; household equipment" (12c.), of uncertain origin, perhaps from Old Norse *hernest "provisions for an army," from herr "army" (see harry (v.)) + nest "provisions" (see nostalgia). Non-military sense of "fittings for a beast of burden" is from early 14c. German Harnisch "harness, armor" is the French word, borrowed into Middle High German. The Celtic words are believed to be also from French, as are Spanish arnes, Portuguese arnez, Italian arnese. Prive harness (late 14c.) was a Middle English term for "sex organs."
harness (v.)youdaoicibaDictYouDict
"to put a harness on a draught animal," c. 1300, from Old French harneschier "make ready, equip, arm," from harnois (see harness (n.)); figurative sense "to control for use as power" is from 1690s. Related: Harnessed; harnessing.