I·dle a. [Compar. Idler superl. Idlest.]
  1. Of no account; useless; vain; trifling; unprofitable; thoughtless; silly; barren. “Deserts idle.”
     Every idle word that men shall speak, they shall give account thereof in the day of judgment.   --Matt. xii. 36.
     Down their idle weapons dropped.   --Milton.
     This idle story became important.   --Macaulay.
  2. Not called into active service; not turned to appropriate use; unemployed; as, idle hours.
     The idle spear and shield were high uphing.   --Milton.
  3. Not employed; unoccupied with business; inactive; doing nothing; as, idle workmen.
     Why stand ye here all the day idle?   --Matt. xx. 6.
  4. Given rest and ease; averse to labor or employment; lazy; slothful; as, an idle fellow.
  5. Light-headed; foolish. [Obs.]
  Idle pulley Mach., a pulley that rests upon a belt to tighten it; a pulley that only guides a belt and is not used to transmit power.
  Idle wheel Mach., a gear wheel placed between two others, to transfer motion from one to the other without changing the direction of revolution.
  In idle, in vain. [Obs.] “God saith, thou shalt not take the name of thy Lord God in idle.”
  Syn: -- Unoccupied; unemployed; vacant; inactive; indolent; sluggish; slothful; useless; ineffectual; futile; frivolous; vain; trifling; unprofitable; unimportant.
  Usage: -- Idle, Indolent, Lazy. A propensity to inaction is expressed by each of these words; they differ in the cause and degree of this characteristic. Indolent denotes an habitual love to ease, a settled dislike of movement or effort; idle is opposed to busy, and denotes a dislike of continuous exertion. Lazy is a stronger and more contemptuous term than indolent.