Random courses

Random Ran"dom, a. 1. 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. [1913 Webster]

Some random truths he can impart. --Wordsworth. [1913 Webster]

So sharp a spur to the lazy, and so strong a bridle to the random. --H. Spencer. [1913 Webster]

2. (Statistics) of, pertaining to, or resulting from a process of selection from a starting set of items, in which the probability of selecting any one object in the starting set is equal to the probability of selecting any other. [PJC]

3. (Construction) of unequal size or shape; made from components of unequal size or shape. [PJC]

{at random} in a manner so that all possible results have an equal probability of occurrence; for processes, each possible result is counted separately although the same type of result may occur more than once .

{Random courses} (Masonry), courses of stone 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. [1913 Webster]