For-tū'i-tōus, a.

a. [Lat. fortuitus, from forte, adv., by chance, properly abl. of fors, fortis, chance, hazard; Fr. fortuit, It. & Sp. fortuito.] Happening by chance; coming or occurring unexpectedly, or without any known cause.

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

So as to throw a glancing and fortuitous light upon the whole. Hazlitt.

Synonyms—Accidental; casual; contingent; incidental. See ACCIDENTAL.