ridingn.

ridingriding: [11] Until 1974 Yorkshire was divided for administrative purposes into three ridings. The word has no connection with ride. It means etymologically ‘third part’. It was borrowed from Old Norse thrithjungr ‘third part’, a derivative of thrithi ‘third’. Its original English form was *thrithing, later thriding or triding, and it eventually lost its initial t through assimilation into the t of the preceding east and west.=> threeriding (n.2)one of the three districts into which Yorkshire was divided, late 13c., from late Old English *þriðing, a relic of Viking rule, from Old Norse ðriðjungr "third part," from ðriði "third" (see third). The initial consonant merged with final consonant of preceding north, west, or east.riding (n.1)c. 1300, verbal noun from ride (v.). Meaning "teasing, annoying" is from 1927. Riding-hood, worn by women when riding or exposed to weather, is from mid-15c.