What does "random" mean?

Random: A roving motion; course without definite direction; want of direction, rule, or method; hazard; chance; -- commonly used in the phrase at random, that is, without a settled point of direction; at hazard. Counsels, when they fly At random, sometimes hit most happily. Herrick. O, many a shaft, at random sent, Finds mark the archer little meant ! Sir W. Scott.

Additional senses

  1. 2.Distance to which a missile is cast; range; reach; as, the random of a rifle ball. Sir K. Digby.
  2. 3.(Mining) The direction of a rake-vein. Raymond.
  3. 4.Going at random or by chance; done or made at hazard, or without settled direction, aim, or purpose; hazarded without previous calculation; left to chance; haphazard; as, a random guess. Some random truths he can impart. Wordsworth. So sharp a spur to the lazy, and so strong a bridle to the random. H. Spencer. Random courses (Masonry), courses of unequal thickness. -- Random shot, a shot not directed or aimed toward any particular object, or a shot with the muzzle of the gun much elevated. -- Random work (Masonry), stonework consisting of stones of unequal sizes fitted together, but not in courses nor always with flat beds.

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