D defs.my
Entry 2 senses Webster, 1913

Fortuitous

/fôr-to͞o'-ĭt-əs/ · For·tu·i·tous · IPA /foɹˈt͡ʃu.ɪ.tɪs/
01 a. Happening by chance; coming or occuring unexpectedly, or without any known cause; chance; as, the fortuitous concourse of atoms.
  1. 1.
    Happening by chance; coming or occuring unexpectedly, or without any known cause; chance; as, the fortuitous concourse of atoms.
    “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.
  2. 2.
    Happening independently of human will or means of foresight; resulting from unavoidable physical causes.(LAw)