Etymology Dictionary

IDLE,  unemployed, useless, unimportant.  (E.)   M. E. idel, Chaucer, C. T. 2507, 12572; hence the phr. in idel = in vain, id. 12576.—A. S. ídel, vain, empty, useless; Grein, ii. 135. + Du. ijdel, vain, frivolous, trifling. + Dan. idel, sheer, mere. + Swed. idel, mere, pure, downright. + G. eitel, vain, conceited, trifling; O. H. G. ítal, empty, useless, mere.   β. The orig. sense seems to have been 'clear' or 'bright;' hence, pure, sheer, mere, downright; and lastly, vain, unimportant.   The A. S. ídel exactly answers to the cognate Gk. ἰθαρός, clear, pure (used of springs), a scarce word, given in Curtius, i. 310, which see.—✔IDH, to kindle; cf. Skt. indh, to kindle; whence Gk. αἴθειν, to burn, αἰθήρ, upper (clear) air, αἴθρα, clear sky; also A. S. ád (for aid ), a burning, funeral pile, O. H. G. eit, a funeral pile, eiten, to burn, glow.   See Æther.   Der. idl-y; idle, verb; idl-er; idle-ness, Ormulum, 4736, from A. S. ídelnes, Grein, ii. 135.