-fortuitous-

a. [ L. fortuitus; akin to forte, adv., by chance, prop. abl. of fors, fortis, chance. See Fortune. ] 1. Happening by chance; coming or occuring unexpectedly, or without any known cause; chance; as, the fortuitous concourse of atoms. [ 1913 Webster ]

It was from causes seemingly fortuitous . . . that all the mighty effects of the Reformation flowed. Robertson. [ 1913 Webster ]

So as to throw a glancing and fortuitous light upon the whole. Hazlitt. [ 1913 Webster ]

2. (LAw) Happening independently of human will or means of foresight; resulting from unavoidable physical causes. Abbott.

Syn. -- Accidental; casual; contingent; incidental. See Accidental.

-- For*tu"i*tous*ly, adv. -- For*tu"i*tous*ness, n. [ 1913 Webster ]