aleatory
Depending on the throw of a die; random, arising by chance.
Soon the snow will close on us; we are here some twenty miles - twenty-seven, they say, but this I profoundly disbelieve - in the woods; communication by letter is slow and (let me be consistent) aleatory; by telegram is as near as may be impossible.
Produced with an element of chance (aleatoricism).
Where it comes from
From Latin āleātōrius, from āleātor (“dice-player”), from ālea (“a die”).
Adapted from the Wiktionary entry aleatory (CC BY-SA 4.0).