random

adv. accidentally, by chance, fortuitously, without prior planning

adj. chance, fortuitous, accidental, unplanned

The word random is used to express lack of order, purpose, cause, or predictability in non-scientific parlance. A random process is a repeating process whose outcomes follow no describable deterministic pattern, but follow a probability distribution.The term randomness is often used in statistics to signify well defined statistical properties, such as lack of bias or correlation. Monte Carlo Methods, which rely on random input, are important techniques of computational science. Random selection is an official method to resolve tied elections in some jurisdictions, and is even an ancient method of divination, as in tarot, the I Ching, and bibliomancy. In the Book of Numbers, God orders Moses to divide the land of Israel by random selection.
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Adjective
1. lacking any definite plan or order or purpose; governed by or depending on chance; "a random choice"; "bombs fell at random"; "random movements"
(antonym) nonrandom
(similar) ergodic
2. taken haphazardly; "a random choice"
(similar) unselected

adj. random, chance, fortuitous, accidental, unplanned

(n.)
The direction of a rake-vein.
  

(n.)
Force; violence.
  

(n.)
Distance to which a missile is cast; range; reach; as, the random of a rifle ball.
  

(n.)
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.
  

(a.)
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.