Englishaccidentally
adverb
we met accidentally |
they accidentally set off a smoke alarm:
fortuitously, by accident, by chance, by a mere chance, by a twist of fate, adventitiously, as luck would have it, by a fluke, flukily, coincidentally, by coincidence, serendipitously;
by a happy chance, by good fortune, by a piece of luck;
unexpectedly;
unintentionally, inadvertently, involuntarily, unpremeditatedly, unthinkingly;
unwittingly, unknowingly, unconsciously, subconsciously, unawares;
by mistake, mistakenly, misguidedly;
North American by happenstance.
accidentally Oxford Dictionary of English