Word Origin & History
O.E. receleas "careless, thoughtless, heedless," earlier reccileas, from -leas "-less" + *rece, recce "care, heed," from reccan "to care," from W.Gmc. *rokijanan (cf. O.N. rækja "to care for," O.H.G. giruochan "to care for, have regard to," Ger. geruhen "to deign," which is infl. by ruhen "to rest").
No known cognates outside Gmc. The same affixed form is in Ger. ruchlos, Du. roekeloos "wicked." Root verb reck (O.E. reccan) is passing into obscurity. The -k- sound is probably a northern influence from O.N. cognate roekja.