Synonyms for Fortuitously:

• adj.

  •accidentally (adjective)
  • fortuitously,
  • by mistake,
  • unwittingly.

• adv

  •by chance (adverb)
  • unexpectedly,
  • incidentally.

• adv.

  •accidentally (adverb)
  • causelessly,
  • fortunately,
  • accidentally,
  • fatally,
  • unintentionally,
  • randomly,
  • adventitiously,
  • aimlessly,
  • haphazardly.
  •by chance (adverb)
  • by coincidence,
  • by a fluke,
  • out of the clear blue sky,
  • for some reason.
  •fortunately (adverb)
  • blessedly,
  • favorably,
  • advantageously,
  • successfully,
  • auspiciously.
  •incidentally (adverb)
  • by the way,
  • Obiter,
  • casually.
  •successfully (adverb)
  • Thrivingly,
  • swimmingly,
  • profitably,
  • strongly,
  • well,
  • victoriously,
  • Flourishingly,
  • prosperously,
  • triumphantly.

• n.

  •as luck would have it (noun)
  • as luck would have it.

• Other synonyms:

  •
  • unnecessarily.
  •Other relevant words:
  • somehow,
  • inadvertently,
  • perchance,
  • casual,
  • unsystematically,
  • unpredictably,
  • indiscriminately,
  • serendipitously,
  • abruptly,
  • irregularly,
  • at random,
  • occasionally,
  • erratically,
  • suddenly,
  • oddly,
  • indeterminately,
  • without design,
  • random,
  • Incidently,
  • Contingently,
  • happily,
  • unforeseeably,
  • Unpremeditatedly,
  • now and then,
  • coincidentally,
  • arbitrarily,
  • stochastically,
  • indefinitely,
  • accidental,
  • by accident.

Antonyms for Fortuitously:

• adv.

  • Other antonyms:
    unfortunately, regrettably, unluckily, alas.