古英語のreccan, to be concerned, to be attentiveから、原語ゲルマン語*rokijana, to be concerned, to be attentiveから、PIE*reg, to be attentive, to be helpfulから、おそらくこのインド?ヨーロッパ語根PIE*reg, to straight, to manageの原義から、語源的にはregregate, regalと同じ。
And in that very moment, away behind in some courtyard of the City, a cock crowed. Shrill and clear he crowed, recking nothing of wizardry or war, welcoming only the morning that in the sky far above the shadows of death was coming with the dawn. [J.R.R. Tolkien, "Return of the King," 1955]The -k- sound is probably a northern influence from Norse. No known cognates outside Germanic. "From its earliest appearance in Eng., reck is almost exclusively employed in negative or interrogative clauses" [OED]. Related: Recked; recking.